Chevron North Sea Limited Rosebank Development Project PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS WITH ADDENDUM ROS-PGEN-MEC-STD-CHV-0000-00036-01 (ADDENDUM) H03 21-OCT-2013 ISSUED FOR USE H02 12-AUG-2013 ISSUED FOR USE H01 05-APR-2013 ISSUED FOR USE REV DATE DESCRIPTION APPROVED BY: COMPANY APPROVAL: DATE: DATE: ORIG CHK APPR Project Area Discipline Type Originator Package Sequence No. Revision ROS PGEN MEC STD CHV 0000 00036-00 H03 DOCUMENT CONTROL NO. PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS APPLICATION: TOPSIDES This document is the confidential property of Chevron U.S.A. Inc. Neither the whole nor any part of this document may be disclosed to any third party without the prior written consent of Chevron U.S.A. Inc. Neither the whole nor any part of this document may be reproduced, stored in any retrieval system or transmitted in any form or by any means (electronic, mechanical, reprographic, recording or otherwise) without the prior written consent of Chevron U.S.A. Inc. Rev Date 04/05 08/10 (E) August 2010 (E) Description Author Sponsor Initial release BOSD BOSD Errata change: Updated titles of Company drawings GF-C87280 and GF-C99694 BOSD BOSD © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 1 of 48 General Specification for Pressure Vessels PVM-SU-8.00 CONTENTS 1.0 Scope ..........................................................................................................................4 1.1 ......Responsibilities ................................................................................................4 1.2 ......Conflicts and Exceptions ..................................................................................4 2.0 References ..................................................................................................................5 2.1 ......Purchaser Documents ......................................................................................5 2.2 ......Standard Drawings ...........................................................................................5 2.3 ......Industry Standards ...........................................................................................5 3.0 General Requirements ...............................................................................................7 4.0 Materials ......................................................................................................................8 5.0 Engineering ................................................................................................................8 5.1 ......General Engineering ........................................................................................8 5.2 ......Design Requirements .......................................................................................9 5.3 ......Shell .................................................................................................................9 5.4 ......Heads and Transitions ...................................................................................10 5.5 ......Nozzles, Manways, Bosses and Other Openings ..........................................10 5.6 ......Internals ..........................................................................................................13 5.7 ......External Attachments .....................................................................................15 5.8 ......Vessel Supports .............................................................................................16 6.0 Fabrication ................................................................................................................19 6.1 ......General ...........................................................................................................19 6.2 ......Qualification of Welding Procedures and Welders .........................................20 6.3 ......Welding Processes .........................................................................................21 6.4 ......Production Welding ........................................................................................22 6.5 ......Heat Treatment and Stress Relieving ............................................................23 7.0 Inspection and Testing ............................................................................................23 7.1 ......General ...........................................................................................................23 7.2 ......Non Destructive Examination .........................................................................24 7.3 ......Radiographic Inspection .................................................................................24 7.4 ......Hydrostatic Pressure Testing .........................................................................25 7.5 ......Pneumatic Pressure Testing ..........................................................................26 8.0 Protective Coatings .................................................................................................26 9.0 Identification and Markings .....................................................................................27 10.0 Preparation for Shipment and Storage ..................................................................28 11.0 Documentation Requirements ................................................................................29 Appendix I: ...........................................................................................................................32 Appendix II: ..........................................................................................................................35 Appendix III: .........................................................................................................................37 Appendix IV: .........................................................................................................................38 August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 2 of 48 General Specification for Pressure Vessels PVM-SU-8.00 Appendix V: ..........................................................................................................................44 Appendix VI: .........................................................................................................................47 August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 3 of 48 General Specification for Pressure Vessels 1.0 PVM-SU-8.00 SCOPE 1. This specification governs pressure vessels provided in accordance with the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1; Pressure Vessels, hereafter referred to as the ASME Code. Carbon steel vessels are generally limited to wall thickness of 1-1/2" (38 mm) or less and design temperatures of 650F (343C) or less. 2. This specification may be supplemented with other requirements such as vessel data sheets (see PVM-DS-8.00 or approved equivalent), Project Technical Requirements, Standard Drawings and/or other supplementary specifications (for vessels in specific services, such as threephase separators). 3. The set of combined documents in Section 1.0 item 2, above, define the minimum acceptable requirements for the design, fabrication, inspection and testing of unfired pressure vessels suitable for installation on an offshore platform. 4. Company reserves the right to procure pressure vessels in accordance with the ASME Code even though they may be outside the formal scope of ASME Code, for instance due to size or pressure rating. Such pressure vessels shall conform to all ASME Code requirements, except for application of the ASME Code Stamp and National Board Registration. 5. The most recent issue of the standards, specifications and codes (using the latest addenda issued through the date of this agreement) listed in Section 2.0 shall be considered as a part of this Specification. 6. In addition to project technical requirements, pressure vessels shall meet all requirements of the governmental authorities having jurisdiction at the location where the pressure vessel is to be installed, as stated in the Agreement, Contract, or Purchase Order, as applicable. 7. Vessels shall be designed to meet the operating and design conditions listed on attached Vessel Data Sheets. Shell diameter, length and nozzle sizes shown are considered as minimum unless defined otherwise. 8. Pressure vessels with thickness greater than 1.5" (38 mm) shall meet the additional requirements specified in Appendix II. 9. Pressure vessels constructed of stainless steel materials shall meet the additional requirements specified in Appendix III. 10. Pressure vessels constructed of stainless steel clad carbon steel shall meet the additional requirements specified in Appendix IV. 11. Vessels shall be equipped with all attachments such as nozzles, manways, tray support rings, and insulation clips. 1.1 Responsibilities 1. Contractor shall be solely responsible for providing complete and operable pressure vessels in full accordance with all applicable industry codes and standards, government regulations and project technical requirements. 2. Written permission must be obtained before any work is subcontracted. 1.2 Conflicts and Exceptions 1. All conflicts between this specification or other technical requirements and the applicable codes and standards shall be submitted in writing to Company for resolution. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 4 of 48 General Specification for Pressure Vessels PVM-SU-8.00 2. All exceptions to this specification or other technical requirements shall be submitted in writing to Company for consideration and possible approval. 2.0 REFERENCES 1. The following documents are referenced herein and are considered part of this specification. 2. Use the edition of each referenced document in effect on the date of the publication of this specification. 2.1 2.2 2.3 Purchaser Documents COM-SU-2.02 Materials and Application of Painting and Protective Coatings PVM-DS-8.00 Data Sheet for Pressure Vessels SID-SU-5106 Safety in Designs Standard Drawings GA-C1266 Horizontal Pressure Vessel Fabrication Tolerances GA-C1267 Vertical Pressure Vessel Fabrication Tolerances GD-M13909 Standard Clips GF-C14311 Standard Pressure Vessel Nozzles GC-C31554 Standard Detail of Strainer for Bottom Outlet Nozzles GD-C78876 Standard Skirt and Base Details for Vertical Vessels GF-C87280 Standard Manway Cover Davits and Hinges GB-C99772 Standard Ladder Rungs Inside Columns and Vessels GA-C99913 Vortex Breaker for Vessel Liquid Outlets GF-C99694 Standard Details of Saddles for Horizontal Vessels GB-C99945 Standard Support Legs for Vertical Vessels GD-C99663 Standard Connections and Welding Details for Clad Steel Vessels GF-C1030 Standard Nozzles and Manholes for Thick-Walled Pressure Vessels Industry Standards American Institute of Steel Construction (AISC) Manual of Steel Construction American Society of Civil Engineers (ASCE) 7 August 2010 (E) Building Code Requirements for Minimum Design Loads in Buildings and Other Structures © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 5 of 48 General Specification for Pressure Vessels PVM-SU-8.00 American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Section II, Materials Note: SFA requirements for welding consumables may be located in Part C of Section II Section VIII,Rules for Construction of Pressure Vessels, Division 1 Section VIII, Rules for Construction of Pressure Vessels, Division 2, Alternative Rules Section IX, Qualification Standard for Welding and Brazing Procedures, Welders, Brazers, and Welding and Brazing Operators B1.1 Unified Inch Screw Threads B16.5 Pipe Flanges and Flanged Fittings B16.47 Large Diameter Steel Flanges, NPS 26 Through NPS 60 B31.3 Process Piping SFA-5.4 Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding SFA-5.9 Specification for Bare Stainless Steel Welding Electrodes and Rods American Society for Testing and Materials (ASTM) SA-36 Carbon Structural Steel SA-234 Pipe Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service SA-263 Specification for Corrosion-Resisting Chromium Steel-Clad Plate, Sheet, or Strip SA-264 Specification for Corrosion-Resisting Chromium-Nickel Steel-Clad Plate, Sheet, or Strip SA-285 Pressure Vessel Plates, Carbon Steel, Low and Intermediate Tensile Strength SA-325 High-Strength Bolts for Structural Steel Joints SA-435 Specification for Straight-Beam Ultrasonic Examination of Steel Plates SA-578 Specification for Straight-Beam Ultrasonic Examination of Plain and Clad Steel Plates for Special Applications American Welding Society (AWS) D1.1 Structural Welding Code - Steel A4.2 Standard Procedures for Calibrating Magnetic Instruments to Measure the Delta Ferrite Content of Austenitic and Duplex Ferritic-Austenitic Stainless Steel Weld Metal A4.3 Standard Method for Determination of the Diffusible Hydrogen Content of Martensitic, Bainitic and Ferritic Steel Weld Metal Produced by Arc Welding August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 6 of 48 General Specification for Pressure Vessels PVM-SU-8.00 Code of Federal Regulations 46 CFR Part 50 General Provisions 46 CFR Part 54 Pressure Vessels 46 CFR Part 57 Welding and Brazing National Association of Corrosion Engineers (NACE) MR-01-75 Sulfide Stress Cracking Resistant Metallic Material for Oil Field Equipment Process Industry Practices (Drawings) (PIP) PIP VEFV1103 Vessel Grounding Lug PIP VESV1003 Fabrication of Welded Vessels and Tanks to be Lined Steel Structures Pointing Council SSPC SP-5 White Metal Blast Cleaning SSPC SP-10 Near-White Blast Cleaning Welding Research Council WRC 107/297 Local Stresses in Cylindrical Shells Due to External Loadings on Nozzles Welding Journal Research Supplement Stresses in Large Horizontal Cylindrical Pressure Vessels on Two Saddle Supports, by L.P. Zick, Revised 1971. 3.0 GENERAL REQUIREMENTS 1. The design, materials, fabrication, inspection, testing and documentation of pressure vessels shall be in full accordance with the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 or Division 2; Pressure Vessels, and project technical requirements. All Addenda issued through the date of the Agreement, Contract, or Purchase Order shall apply in full. 2. Unless specified otherwise, Contractor shall be solely responsible for detailed process design. a. Any vessel sizing or design criteria provided by Company, including diameter, length, nozzle sizing, internal configurations, etc., shall be considered preliminary and confirmed by Contractor. b. Reduction of Company specified sizing or design criteria shall not be acceptable without prior Company approval, in writing. 3. Unless specified otherwise by Company, pressure vessels shall have a minimum service life of 20 years, and internals that are readily replaceable shall have a minimum service life of 10 years. 4. Pressure vessels specified for “sour service” shall be in accordance with NACE MR-01-75 and the additional requirements of Appendix VI. 5. All flanges shall be in accordance with the latest edition of ASME B16.5, or ASME B16.47. 6. Piping outside the limits of the ASME Code, if included, shall conform to ASME B31.3. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 7 of 48 General Specification for Pressure Vessels 4.0 PVM-SU-8.00 MATERIALS 1. Materials and construction for pressure vessels shall conform to the ASME Code and with the requirements of this Specification, including the applicable Appendices, unless otherwise indicated on the Company-approved vessel drawings. 2. Any recommended material substitutions that do not meet the above requirements shall be submitted to the Company for review and approval. For example, Contractor may, with Company approval, upgrade material in lieu of impact testing. 3. Castings shall be prohibited, unless agreed to by the Company in writing. 4. All materials shall be new and free from mill scale. 5. Impact test exemption per Division 1, Paragraph UG-20 (f), is not allowed except for P1, Group 1 material up to 1/2" (13 mm) thick. 5.0 ENGINEERING 5.1 General Engineering 1. Contractor shall be responsible for the detailed mechanical design of pressure vessels in accordance with the ASME Code and other Technical Requirements. 2. The minimum acceptable internal corrosion allowance shall be 1/8" (3 mm) for all “wetted” components, including but not limited to the vessel shell, heads, nozzles, internals, etc., unless specified otherwise. a. If the vessel is to be clad, no corrosion allowance is necessary. b. Internals that are fabricated from stainless steel or corrosion resistant high alloy steels shall be exempt from this corrosion allowance requirement. c. Internal rings, supports, baffles, vortex breakers, miscellaneous plates and structural shapes, piping supports, etc., shall have a minimum thickness of 1/4" (6 mm) exclusive of corrosion allowance. 3. For internals "wetted" or exposed on both sides, the corrosion allowance shall be at least 50% greater than the single side corrosion allowance specified for the shell. 4. Internals that are bolted and easily removable from the vessel shall be exempt from the 150% corrosion allowance requirement, i.e., they shall be provided with the same corrosion allowance as the shell. 5. The minimum thickness of all pressure containing components, including shells, heads, nozzle necks, piping, etc., shall be 1/4" (6 mm), including corrosion allowance. The minimum thickness of internals shall be 1/4" (6 mm), including corrosion allowance. 6. A corrosion allowance of 1/8" (3 mm) shall be added to the calculated thickness of skirts or support legs attached to vertical vessels and to saddles that support horizontal tanks or drums. 7. If provided, Company General Arrangement Drawing shall be considered preliminary and Company will finalize arrangement details during the approval process. Company reserves the right to revise nozzle locations, at no additional cost, up to the point of actual fabrication, i.e., until the shell or head penetrations are cut. 8. Pressure vessels shall be designed and fabricated to facilitate maintenance, repairs and alterations, in particular on adjustable or removable internals. 9. When specified on the vessel data sheet, vessels designed for internal pressure shall be stamped for external pressure, as noted. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 8 of 48 General Specification for Pressure Vessels PVM-SU-8.00 10. The design pressure of equipment in vacuum service or which may be subjected to vacuum during reasonable start-up, operating, shutdown or upset conditions, shall be full vacuum except where the Contractor can demonstrate that an economical alternative design will not allow full vacuum to occur. 11. The following Minimum Design Metal Temperatures (MDMT) and coincident pressures shall be indicated on both the vessel nameplate and the Manufacturer's Data Report. a. MDMT at Maximum Allowable Working Pressure (MAWP). b. Lowest allowable MDMT and coincident maximum pressure 12. Vessels subject to steam-out shall be designed to withstand the steam-out pressure/temperature condition and external pressure of 7.5 psi (0.5 bar) at 450°F (232C). 5.2 Design Requirements 1. Contractor's design shall accommodate all of the following requirements, as applicable. • Fabrication/Handling Loads • Internal Design Pressure • External Design Pressure • Ocean Transportation Accelerations • Wind Pressure Loads • External Nozzle Loads • Support Clip Point Loads • Thermal Expansion • Hydrostatic Test • In-Service Flooded Condition • Sand Loadings 2. Static head pressures shall be included in the design pressure. 3. The MAWP shall be based on the actual metal thickness less corrosion allowance. 4. The maximum allowable pressure shall be limited by the shell or heads, not by minor parts such as flanges, nozzle necks, reinforcing pads, piping, fittings, or manways. The design report shall clearly identify the limiting component. 5. Vessels in vacuum service shall be designed for a minimum internal pressure of 50 psig (3.45 bar). 6. MDMT shall be as shown in vessel datasheet, which shall apply to both pressure containing and vessel support components. MDMT shall not be warmer than 50F (10C). 7. The shells of larger diameter horizontal vessels shall have sufficient thickness and/or adequate stiffness to be structurally stable when full of water at atmospheric pressure. 8. Temporary and permanent stiffening shall be provided to prevent distortion of the vessel during manufacture and transport 9. Vessel supports shall be designed for wind, seismic and transportation loads per Section 5.8. 10. Fabrication tolerances shall comply with Standard Drawings GA-C1266 and GA-C1267. 5.3 Shell 1. Pressure vessel shells shall be fabricated from rolled and welded plate. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 9 of 48 General Specification for Pressure Vessels PVM-SU-8.00 2. For vessels 24" (610 mm) and smaller in outside diameter, seamless pipe in accordance with ASME Code may be utilized. 3. Vessels made from pipe shall have wall thicknesses that account for the mill under thickness tolerance allowed by the piping Code and ASTM specifications. 4. Longitudinal seams on horizontal vessels shall be located a minimum of 30 degrees above the horizontal plane through the centerline of the vessel. Long seams shall be staggered about the vessel vertical centerline between adjacent shell cans. 5.4 Heads and Transitions 1. Unless specified otherwise, all vessel heads shall be 2:1 ellipsoidal type with straight flanges a minimum of 1-1/2" (38 mm) long. 2. For vessels 24" (610 mm) and smaller in outside diameter, weld caps in accordance with the ASME Code may be utilized. 3. Toriconical transition sections are preferred. Conical transitions are permitted only when agreed to by the Company. 4. When conical transitions are used: a. Joint efficiency of 1 is not permitted, due to difficulty in examining the joints. b. Stiffening rings shall not be located closed than 6" (150 mm) from the weld seam of conical transitions. 5.5 Nozzles, Manways, Bosses and Other Openings 1. Unless specified otherwise by Company, all vessel nozzles shall be flanged, with a minimum size of 1-1/2" NPS (DN 40). 2. Flanged nozzles smaller than 1-1/2" NPS (DN 40) shall not be allowed unless specifically approved in writing by Company, and shall never be smaller than 3/4" NPS (DN 20). 3. Threaded connections shall not be allowed unless specified or specifically approved in writing, by Company. a. If approved, threaded connections shall be 6000# forged steel full couplings as a minimum. b. Threaded connections shall be limited to either 1/2" or 3/4" NPS (DN 15 or 20). c. Threaded connections shall have their threads chased after installation or postweld heat treatment. d. Threaded connections shall not be acceptable for use on internally coated or clad vessels or stainless steel vessels. 4. Weld-o-lets, Thread-o-lets, and Sock-o-lets shall not be acceptable for vessel connections. 5. “Set-on" nozzle designs are not acceptable. 6. All shell and head attachments, including nozzle necks, manway necks, threaded couplings, reinforcing pads and clips shall be located a minimum of 2" (50 mm) from vessel longitudinal and circumferential seams. a. When unavoidable and approved in writing by the Company, attachments may cover a welded joint. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 10 of 48 General Specification for Pressure Vessels PVM-SU-8.00 b. However, prior to covering the joint, the seam weld shall be ground flush and 100% radiographed to a minimum of 6" (150 mm) beyond each side of the attachments. 7. Nozzles shall be either long weld neck flanges, or of built-up construction from pipe nozzle necks and flanges. a. Long weld neck flanges are preferred by Company for all nozzles 3" (DN 80) and smaller. b. Flanges used in built-up construction shall be forged steel weld neck type, bored to match the inside diameter of the pipe nozzle neck. c. Socket welded or slip-on flanges shall not be acceptable, except on manways. d. Studded pad-type nozzles shall not be permitted 8. Unless specified otherwise, ANSI Class 150 through Class 600 series flanges shall be raised face (RF) type, and Class 900 and above shall be ring type joint (RTJ) flanges. 9. On nozzles and manways having tongue and groove facing, the groove shall be on the vessel unless the flange face is directed downward, in which case the tongue shall be on the vessel. 10. Vessel nozzle neck thickness shall be in accordance with the ASME Code, but with the following minimum thickness requirements: Nominal Diameter (DN) Nom. Pipe Size: Min. Schedule: 40 1-1/2" XXS 50 to 80 2" to 3" 160 100 4" 120 150 to 250 6" to 10" 80 300 to 400 12" to 16" 60 450 to 500 18" to 20" 30 600 24" 40 11. Nozzle outside projections shall be sufficient for the removal of a properly sized stud from the back side of all flange bolt holes, i.e., between the back of the flange and the vessel shell, head or reinforcing pad. As a minimum, all nozzles shall project at least 6" from the vessel outside diameter to the flange face. 12. Nozzle Design Details and Reinforcement a. Nozzle design details and reinforcement shall conform to Standard Drawing GF-C14311. b. As an alternative to the Standard Drawing, nozzle reinforcement calculation per current Code is acceptable, provided the design conforms to all the other requirements listed in this specification. 13. Nozzles with Inside Projections a. Vessel drains and liquid outlets shall be flush with the inside surface of the vessel and shall be provided with vortex breakers, unless otherwise shown on the vessel drawings. Flush designs may be required to remove internals. b. Vessel drains requiring a strainer shall conform to GC-C31554. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 11 of 48 General Specification for Pressure Vessels PVM-SU-8.00 c. The projection of process connection nozzles shall be established with due consideration of sand or scale accumulation. d. Company approval of nozzle projections shall be required. e. Inner edges of nozzles, manway necks, and other pressure vessel penetrations shall be ground smooth to 1/8" (3 mm) minimum radius. 14. Reinforcing Pads and Saddles a. All reinforcing pads and saddles shall be drilled and tapped for a 1/4" NPT (DN 8) telltale hole. b. Telltale holes shall be located on the low axis of the reinforcing pad. c. Two (2) telltale holes shall be provided on all nozzles greater than 24" NPS (DN 600), and on all split or segmental reinforcing pads. d. A preliminary compressed-air and soap-suds test shall be made in accordance with Paragraph UW-15(d) of the ASME Code. 15. Manways and Manholes a. Manways shall be provided to access each vessel section that requires cleaning or maintenance, and to permit the removal of internal components. b. Designs shall comply with Standard Drawing GF-C87280. c. Unless specified otherwise, manway size shall be 20" NPS (DN 500) for vessels with inside diameters of 4'-0" (1220 mm) and less, and 24" NPS (DN 600) for vessels with inside diameters greater than 4'-0" (1220 mm). d. A grab bar shall be provided inside the vessel above the manway to facilitate vessel entry, as well as individual rung ladders below. e. All manways and handholes, as well as nozzles designated as "spare", shall be provided with blinds, including studs, nuts and gaskets. f. Handhole blinds shall be provided with two (2) handles. g. All nuts, bolts and washers shall be carbon steel coated with Type II Class 8 chromated/ cadmium plating. h. Manway blinds shall be hinged or davited, complete with a handle. i. Nozzle, manway and handhole flange bolt holes shall straddle vessel normal centerlines unless noted otherwise. j. Handholes shall be circular with an 8-inch (203 mm) minimum interior diameter. 16. Davits a. Davits shall be designed such that no adjustments are necessary to align the blind flange with its mating flange. b. Davits shall not sag. c. Davits shall be fitted with grease fittings in the swivel. d. Davit arms fabricated from pipe shall be capped to prevent intrusion of moisture. 17. Nozzles, manways, handholes and couplings shall be attached to the vessel with full penetration welds, including reinforcing pad to nozzle neck welds. 18. The orientations of critical nozzles shall be shown on the Vessel Data Sheet. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 12 of 48 General Specification for Pressure Vessels PVM-SU-8.00 19. The Contractor shall be responsible for ensuring that nozzle locations will allow for easy access to various control instruments and valves. 20. The use of gooseneck nozzles (nozzles with elbows, tees, or any other weld fitting) shall be subject to Company approval. 21. Vessel Nozzle Loads a. Vessel/Nozzle connections shall be capable of withstanding reasonable piping loads. b. Company reserves the right to supply actual piping loads as they become available. c. Local stress at the nozzle connection shall be calculated using WRC 107/297 when applicable, or ASME Section VIII, Div 2, Appendix 4. Extrapolation of geometric parameter curves in WRC 107/297 shall not be permitted. 5.6 Internals 1. Internal non-pressure-containing parts, such as trays and catalyst support beams, internal equipment, such as cyclones and grids, and attachments welds to vessel, shall be designed using allowable stress for material and temperature specified in ASME Section II, Part D, as applicable. 2. Contractor shall provide all internals in accordance with the following requirements. a. Internals furnished by others shall be installed by the Fabricator. b. Baffles, partitions, and other parts shall be designed to accommodate differential thermal expansion between vessel shell and internal parts. c. Baffles, partitions, and other parts shall be designed to avoid trapping water or flammable liquids that cannot be drained or purged. d. Internal ladders shall comply with Standard Drawing GB-C99772, 3. An inlet diverter shall be provided on the inlet nozzles of vessels that handle multi-phase fluids, e.g., separators, scrubbers, knockout drums, etc. In addition, inlet diverters shall be provided for erosive fluids and for high velocity fluids such as those downstream of high pressure let-down valves. a. Inlet diverter design shall utilize either box or pipe type construction. b. Three-phase vessels shall be equipped with inlet compartmental boxes or baffles with downcomer pipes, to pipe fluid to the interface level. c. Compartmental boxes shall be adequately sized for gas/liquid separation. d. The inlet diverter shall be designed such that no "reflection" of the inlet stream impinges or erodes the vessel shell. e. A wear plate shall be provided on the vessel shell or head if diverter construction directs the inlet fluid against the vessel shell or head. f. Wear plates shall be a minimum of 3/8" (10 mm) thick. g. Wear plate size shall be a minimum of five times the cross sectional area of the inlet nozzle, or 12" (305 mm) greater in radius than the nominal pipe size of the inlet nozzle, whichever is greater. 4. Mist extractors shall be provided to remove entrained liquids from gas streams to a minimum level of 0.1 gallon per million standard cubic feet (MMSCF) at 10 microns () and larger, and shall be sized to maximize turndown capacity. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 13 of 48 General Specification for Pressure Vessels PVM-SU-8.00 a. The design shall base the open area on the Manufacturer's maximum allowable velocity and the governing combination of pressure and flow. b. Materials of construction and all mounting hardware shall be 316L stainless steel. 5. Mist extractors shall be either parallel plate (vane) type or wire mesh mist pad types as specified. If not specified, mist extractors shall be parallel plate (vane) types. 6. Parallel plate (vane) type mist extractors shall be provided with a liquid collection pan, including a liquid seal, to allow proper drainage to the liquid section. 7. Wire mesh mist pad extractors shall have a mist pad density of 11 pounds per cubic foot (#/ft3) (176 kg/m3) minimum, and mesh thickness of 6" (150 mm) minimum. 8. Contact the Company for additional requirements on vapor/liquid separators and scrubbers. a. Mist pads shall be of 316L stainless steel construction, including mesh, support grid, distribution plates and all mounting hardware. b. Mist pad assemblies shall be accessible for inspection and maintenance, and easily removable for cleaning or replacement. 9. Vortex breakers shall be provided on all liquid outlets that feed process equipment, in particular pumps and hydrocyclones. a. The design of vortex breakers shall comply with Standard Drawing GA-C99913. b. Nozzle inside projection shall be flush with the bottom of the vessel. 10. Vessel drains shall be flush with the bottom of the vessel and shall be provided with vortex beakers unless shown otherwise on vessel drawings. 11. If specified in the vessel data sheet, Contractor shall provide a jetting system for sand removal. a. The system shall consist of a loop-type manifold with Vee-Jet Model H3/8U6550 steel jet nozzles, or Company approved equal, directed at the vessel drains from both sides. b. Minimum inlet nozzle and header size shall be 2" NPS (DN 50). c. All piping shall be schedule 80 thickness as a minimum and shall be adequately supported with stand-offs that are seal welded to the vessel shell. d. All drains shall be covered with a removable sand pan a minimum of 18" in length. e. Jetting system piping shall use flanged spools of such length that they may be readily inserted and removed through the vessel manway(s). 12. Internal stiffener rings shall be seal welded. a. Seal welding details shall be indicated on the Fabricator's approved detailed fabrication drawings. b. Provide a 1-inch (25 mm) skip in the weld at the bottom of an internal pad for a vent. c. Avoid welding over vessel shell welds. 13. Unless specified otherwise, all internal bolting shall be 316 stainless steel, and shall be doublenutted. 14. Vessels installed on a floating production facility (FPF). a. Due to the motions of the FPF, Contractor shall design all vessels to maintain performance comparable to similar vessels installed on a fixed foundation. This will require Contractor to pay close attention to the design of vessel internals and may require the installation of August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 14 of 48 General Specification for Pressure Vessels PVM-SU-8.00 additional baffle plates or other motion suppression internals to maintain acceptable performance. b. Motions for which the equipment should be designed are detailed in the Project Technical Specifications. 15. Mole Sieve Vessels a. Fatigue analysis is typically required for these vessels. b. Structural support beams for mole sieve vessels shall be designed on the basis of a 20 psi (1.4 bar) (minimum) pressure drop from gas flow across the bed. This differential pressure shall be added to the design live and dead loads from other internals. 5.7 External Attachments 1. Fabricator shall provide all external attachments in accordance with the Project Technical Requirements or vessel data sheet. 2. External attachments shall be shop-welded prior to any stress relief. 3. External attachments shall not cover vessel weld seams without prior Company approval. 4. Ladders, platforms, stairways and railings shall conform to SID-SU-5106. 5. Lifting Lugs a. Lifting lugs shall be provided to facilitate handling and installation. b. Horizontal vessels shall be provided with two (2) lugs installed on the top centerline of the shell. c. Vertical vessels shall be provided with two (2) lugs installed on the top. d. Vertical vessels shall be provided with one tailing lug installed at the skirt base plate to facilitate laydown and uprighting of the vessel. e. Lifting lug design shall incorporate a safety factor of 2.0 applied to the vessel total dry weight, including all internals. f. Unless specified otherwise, the lug design load shall include the weight of external attachments such as ladders and platforms. g. Lug design shall be based on a maximum sling angle of 30 degrees from the vertical. h. For vertical vessels, the lug design shall account for shipment of the vessel in the horizontal position and uprighting of the vessel. 6. Clips a. All vertical vessels 6'0" (1.8 m) or more in overall height shall be equipped with clips on the shell and top head to permit the addition of a ladder and platform. b. Pairs of ladder clips shall be provided below the top head seam, above the skirt baseplate and at intervals not exceeding a 12'0" (3.7 m) spacing. c. Clips shall comply with Standard Drawing GD-M13909. 7. Insulation Support a. Unless specified otherwise, Fabricator shall furnish shop-welded insulation supports in accordance with the Project Technical Requirements or vessel data sheet. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 15 of 48 General Specification for Pressure Vessels PVM-SU-8.00 b. Support rings shall be provided on approximately 12'0" (3.7 m) centers projecting to within ½" (13 mm) of the thickness of the insulation. 8. Grounding Lug a. A grounding lug shall be supplied with the vessel. b. Design of the lug shall be in accordance with PIP drawing VEFV1103. 5.8 Vessel Supports 5.8.1 General 1. Vessel supports shall be designed in accordance with the AISC Manual of Steel Construction. a. Support bolting design (size, number, minimum spacing, etc.) shall be based on use of ASTM SA-325 bolting. b. Designs based on other bolting shall require Company approval. 2. Support designs shall comply with Standard Drawings GF-C99694 and GB-C99945. 3. Wind, seismic and transportation loads shall be in accordance with ASCE 7. a. Basic wind speed shall be per Project Technical Requirement. (1) As a minimum, the design wind velocity shall be 100 miles per hour (3-second gust) (160 km/hr). (2) Unless otherwise stated, Exposure Category D (wind from open body of water) shall be assumed. (3) Unless otherwise stated, importance factor for wind load shall be 1.15. b. Seismic coefficients shall be as stated in the Project Technical Requirements. c. Unless otherwise specified by Company, transportation design loads shall be based on a lateral acceleration of 0.65g acting along both the longitudinal axis and the transverse axis, and a vertical acceleration of 1.5g as a minimum. The allowable stress may be increased by 33% for the transportation design condition. 4. Vessels shall be provided with integral self-supporting supports designed to accommodate the following loads and load combinations, without additional support. a. Erect Load with Full Wind Dead load shall include installed weight of the vessel, including internals, platforms, insulation and other permanent attachments. b. Operating Load with Full Wind or Seismic Loads (1) Operating load shall include all dead and live loads, full and zero process liquid levels, full and zero pressures and thrust loads from attached piping. (2) Full and zero liquid level and pressure combinations are required to determine the maximum longitudinal tensile and compressive stresses. c. Field Hydrostatic Pressure Test Load with Partial Wind When a field hydrostatic pressure test is required, the vessel shall be assumed to be full of water and support shall be designed for 50% of the design wind speed (or 25% of the wind load). August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 16 of 48 General Specification for Pressure Vessels PVM-SU-8.00 5. When specified by Company, vessel supports shall be designed to support the vessel completely filled with sand at 3000 pounds per cubic yard (#/yd3)(1800 kg/m3), and simultaneously subjected to the maximum wind load. As a minimum, production separators and test separators shall be designed to meet this requirement. 6. Base plates and rings shall be designed such that the support bearing pressure shall not exceed 750 psi (51.7 MPa). 7. Support steel shall be a minimum of 1/4" (6.4 mm) thick including corrosion allowance. a. A corrosion allowance of 1/8" (3 mm) shall be added to the calculated thickness of skirts, saddles and support legs. b. All support welding shall utilize continuous seal-welded construction, both inside and outside. 5.8.2 Horizontal Vessels 1. Horizontal pressure vessels shall be provided with two (2) structural steel saddles welded to the vessel shell. 2. Additional supports shall not be acceptable without prior written agreement by Company. 3. Saddle design shall include a web plate, base plate, end flanges and stiffening webs as a minimum. a. The contact angle between the saddle and vessel shell shall be between 120 and 150 degrees. b. A reinforcing plate shall be provided between the vessel shell and the saddle, if needed to reduce local concentrated stresses in the vessel wall. c. All saddle reinforcing plate corners shall be radiused to five times the plate thickness, as a minimum. 4. Unless specified otherwise, saddles shall be provided with bolt holes to allow bolted connection to platform steel. a. Saddle bolt holes shall be slotted at one end of the vessel for thermal expansion if the temperature difference between maximum operating condition and minimum ambient condition is greater than 100F (38C). b. If thermal growth between the saddles exceeds 3/8" (10 mm), a slide bearing plate shall be provided between the saddle base plate and the supporting structural member on the platform. c. The slide plate design shall include Teflon™ slide plates and pipe sleeve-type guides. 5. Horizontal vessel shells shall be analyzed in accordance with L. P. Zick's "Stresses in Large Horizontal Cylindrical Pressure Vessels on Two Saddle Supports." 6. In no case shall the distance between the head tangent line and the saddle centerline be greater than 20% of the tangent to tangent length of the vessel. 7. Internal stiffener rings shall not be accepted as a means of stiffening horizontal vessels. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 17 of 48 General Specification for Pressure Vessels 5.8.3 PVM-SU-8.00 Vertical Vessels 1. Vertical vessels shall be provided with a circular skirt-type support designed to comply with the requirements of Standard Drawing GD-C78876. a. Support skirts shall be the same outside diameter as the vessel supported. b. The skirt shall be butt-welded to the knuckle portion of the bottom head, and the weld shall be contoured to blend smoothly into the head. c. The allowable stress value for skirt thickness shall be calculated in accordance with the ASME Code using a weld joint efficiency of 0.55. 2. Unless specified otherwise, skirts shall be provided with bolt holes to allow bolted connection to platform steel. 3. Skirt design shall include a base ring, access openings, high point vents and pipe openings, as follows: a. Skirts shall be provided with a base ring with a minimum thickness of 1/2" (13 mm) and a maximum thickness of 2" (50 mm). (1) If necessary, gusset plates shall be provided to limit the base ring to 2" maximum thickness. (2) Gusset spacing shall be 18" (457 mm) minimum. b. Skirts shall be provided with one (1) access opening. (1) The opening shall be 18" (457 mm) minimum in diameter. (2) Skirt access openings shall be reinforced with a pipe or rolled collar-type sleeve along the perimeter of the opening. (3) The access opening may be oblong on tall skirts, to provide better access. (4) Provisions shall be made so that the skirt will not hold water. c. Skirts shall be provided with a minimum of two (2) vent holes located as close to the bottom head of the vessel as possible. Vent holes shall be 2" (50 mm) in size, evenly spaced around the vessel circumference, and reinforced with pipe sleeves. d. All pipe openings shall be reinforced with pipe sleeves approximately 1" (25 mm) larger in diameter than the largest pipe spool flange, as applicable. e. All reinforcing sleeves shall project 2" (50 mm) beyond the skirt (both internally and externally) or shall be equal in length to the thickness of any fireproofing or insulation to be applied to the vessel, whichever is greater. f. The number of anchor bolts shall be in multiples of four and there shall be a minimum of four. g. The minimum size of anchor bolts for towers shall be 1 inch (25 mm) diameter. h. The minimum size anchor bolts permitted for vessels other than towers shall be 3/4" (19 mm) diameter. August 2010 (E) i. Fillet welds attaching skirts to heads shall have a minimum fillet size of the thickness of the skirt. j. If base rings are fabricated from segments, these shall be joined with full penetration double butt welds. © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 18 of 48 General Specification for Pressure Vessels PVM-SU-8.00 4. Vessels with outside diameters less than or equal to 24" (610 mm) and not exceeding 10'-0" (3.05 m) in overall height may be provided with leg type supports, subject to Company approval. 5. Wind Requirements for Vertical Vessels a. Vertical vessels or columns with H/D ratios exceeding 15 (where H is the length of the vessel from the point of support to the top tangent line and D is the average diameter in the top third of the vessel column) shall be checked for vortex shedding vibrations. b. Critical wind velocity of the vessel shall be greater than 3 times the maximum 10minute sustained wind velocity corrected at the top of the vessel. 6. Unless otherwise specified, deflection at the top of vertical vessels or columns shall be limited to 6 inches per 100 ft (5 mm per meter) of vessel height. 6.0 FABRICATION 6.1 General 1. All Code Category A and B weld joints, including longitudinal and circumferential joints in vessel shells, heads, and nozzles shall be full penetration, double butt welds (Type 1). 2. Where access limitations require the use of single-welded butt joints, the weld detail shall ensure a full penetration weld with a smooth internal surface contour, to obtain radiographs equivalent in quality to double butt welded joints. 3. An acceptable equivalent for Category A and B joints in nozzles, elbows, and single-sided closure seams, is a single welded butt joint with a gas tungsten arc (GTAW) root bead. 4. Vessels with a wall thickness of 1/2" (13 mm) and less may utilize single butt-welded joints, with prior Company approval. a. The weld detail employed shall ensure a full penetration weld utilizing a single "V" or "U" type weld bevel. b. Joints in vessels to be internally coated shall utilize double butt welds regardless of thickness, to assure good coating application. 5. All Code Category C and D weld joints, including attachment welds on nozzles, couplings, and manways, shall be full penetration welds through the vessel wall, including reinforcing pads where used, and shall be welded from both sides. 6. Where access limitations require the use of single-welded joints, the weld detail shall ensure a full penetration weld with a smooth inside surface contour. 7. Back-up strips shall not be used. 8. Vertical downhill welding shall not be permitted. 9. All semi-automatic or fully-automatic welds shall be made utilizing a multi-pass technique. 10. All non-pressure containing welds, both internal and external, shall be full, continuous seal welds. a. Skip or stitch welding shall not be acceptable, except as permitted by Section 6.4 item 8. b. Internal and external attachments to vessels shell or head shall be continuously seal welded. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 19 of 48 General Specification for Pressure Vessels PVM-SU-8.00 11. Welding wire used in submerged arc or metallic inert gas processes shall be stored in such a manner as to avoid contamination by the formation of oxides on the wire surface. 12. Electrodes, wires and fluxes shall be selected to produce welds with mechanical properties not less than that of the base metal. 13. Low hydrogen consumables shall be certified by the electrode manufacturer, or tested by Fabricator to comply with AWS A4.3 H8 or better. 14. An internal gas purge shall be provided for the root pass and the second layer of stainless steel welds for any gas shielded process. 15. Welding shall not be permitted in inclement weather (wind and/or rain) unless both the welder and the work are well protected from the elements. 16. Welding shall not be permitted when the wind velocity exceeds 5 miles per hour (8 km/hr) for gas shielded processes and 10 miles per hour (16 km/hr) for flux shielded processes unless appropriate wind screens are used. 17. Welding (without preheat) shall not be permitted if the relative humidity is above 50%. 18. The minimum required preheat for carbon steel shall be as follows: a. 50°F (10C) if either the ambient temperature or the metal surface temperature is less than 50°F (10C), for thicknesses up to 1.25 inches (32mm). b. 200°F (93C) for thicknesses greater than 1.25 inches (32mm). 19. All welding equipment shall be in good condition and subject to inspection by Company. Any equipment found in need of repair shall be removed from fabrication work until said repair is completed. 20. For pressure vessels that are to be internally lined, fabrication details shall comply with PIP VESV1003. 6.2 Qualification of Welding Procedures and Welders 1. All Weld Procedure Specifications (WPS) and Procedure Qualification Records (PQR) shall be submitted to and approved by the Company prior to any welding. All welding procedures shall be in writing and shall contain the minimum information contained on ASME Section IX Forms QW-482 and 483. 2. Pre qualified procedures will not be accepted for processes other than automatic submerged arc and manual shielded metal arc. 3. The essential variables must be defined in the procedure specification and must be adhered to in production welding. 4. For P1 materials, each WPS shall include a statement indicating the Minimum Design Metal Temperature (MDMT) for which the WPS is qualified. Qualification may be either by Charpy impact testing or by exemption, as provided by paragraph UCS-66 of the ASME Code. 5. Vessels in sour service are subject to the requirements of NACE MR-01-75 (see Appendix VI for additional requirements). All welding procedures must be supported by Procedure Qualification Records that show compliance with the hardness limitations listed in MR-01-75 for weld metal, HAZ, and parent metal. 6. Contractor shall submit a weld map that identifies the proposed welding process for all welds, or types of weld configurations, prior to the start of welding. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 20 of 48 General Specification for Pressure Vessels PVM-SU-8.00 a. The map must identify the Welding Procedure Specification (WPS) for each weld and must show that the WPS assignments are consistent with the Minimum Design Metal Temperature for each weld. b. If requested by Company, Contractor shall provide a welding sequence for critical joints or welds. 6.2.1 Welder and Welding Operator Qualification All welder qualifications and certificates with picture identification shall be submitted to Company for approval prior to any fabrication. 6.2.2 Weld Repair Procedures Fabricator shall prepare weld repair procedures that outline the steps necessary to make cap, through-wall, and partial penetration repairs. All weld repair procedures shall be submitted to Company for approval prior to start of repair work. 6.3 Welding Processes Acceptable weld processes for welding of the pressure envelope and supports shall include the following: • Gas Shielded Flux Core-Arc Welding (FCAW-G) • Gas Metal-Arc Welding (GMAW) • Gas Tungsten-Arc Welding (GTAW) • Shielded Metal-Arc Welding (SMAW) • Submerged-Arc Welding (SAW) 6.3.1 Gas Shielded Flux Core-Arc Welding (FCAW-G) 1. For carbon steel, the maximum wire diameter for FCAW consumable shall be limited to 1/16" (1.6 mm) for out of position welding and 3/32" (2.4 mm) for flat position welding. 2. Electrode diameter shall not exceed 3/32" (2.4 mm) for austenitic stainless steel. 3. One hundred percent ultrasonic inspection is required for all nozzle attachment welds made using FCAW. 6.3.2 Shielded Metal-Arc Welding (SMAW) 1. Low hydrogen electrodes (e.g., E7018) shall be required, except cellulosic SMAW electrodes may be used for the root and hot pass on single-sided butt welds. 2. Coated electrodes shall be stored in dry heated storage bins or cabinets. 3. Cellulosic electrodes shall not be permitted for welds on API flanges. 4. The following electrode classifications shall not be accepted: • E6012 • E6013 • E7014 • E7020 • E7024 • E8013-B2 August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 21 of 48 General Specification for Pressure Vessels 6.3.3 PVM-SU-8.00 Submerged-Arc Welding (SAW) 1. Semi-automatic equipment is not permitted. 2. Weld passes shall not be greater than 3/8" (10 mm) thick. 3. SAW procedure qualification test records shall show the name of the manufacturer and the trade name of the wire and flux used to qualify the procedure. Flux manufacturer's trade name shall be an essential variable. 4. Addition of alloy agents through the flux shall not be acceptable. 5. SAW is not permitted for austenitic stainless steel. 6.4 Production Welding 1. GMAW and TIG welding processes shall be limited to root passes unless specifically approved otherwise by Company in writing. a. All GMAW root welds shall be back gouged to remove all deposited metal prior to the start of welding of the remaining passes. b. The interrupted-arc (short-circuit transfer) GMAW process shall not be used except for the following applications. 1. Root passes on circumferential, longitudinal, or nozzle-to-shell welds only if backgouged and backwelded. 2. Root passes on circumferential piping welds for fabricated nozzles or internal piping. 3. Root passes on nonpressure-containing vessel internals. 2. Nozzles, couplings, and manways shall be attached to the vessel with full penetration welds through the vessel wall, including any reinforcing pads or plate which may be used. 3. All long seams shall clear nozzles, clips, and other external parts by a minimum of 2.0 inches (50 mm). 4. Long seams of trayed vessels shall not be located behind downcomers. 5. Long seams for horizontal vessels shall be located a minimum of 30 degrees above the horizontal plane through the centerline of the vessel. 6. Long seams shall be located such that internal visual inspection can be made with as much of vessel internals in place as possible. 7. Welds are to be chipped or ground flush with the plate on the inside of the vessels where necessary for the passage of trays and baffles. Melting out of the reverse side of the weld shall not be permitted. 8. Internal and external attachments to vessel shell or head shall be continuously seal welded (unless prohibited by the ASME Code), except that a 1" (25 mm) skip in the bottom of an internal pad shall be made for a vent. Fabricator shall include weld details on approved detailed fabrication drawings. 9. Jigs shall be utilized on direct connected instrument nozzle pairs to accurately set dimensions and ensure that flange faces are parallel. 10. All welds shall be thoroughly cleaned after each pass by power wire brushing to remove all slag, splatter, coatings and dirt. a. All joints welded from both sides shall be back chipped or back gouged to sound metal before continuing welding on the second side of the joint. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 22 of 48 General Specification for Pressure Vessels PVM-SU-8.00 b. The use of needle guns to remove slag from finished welds shall be prohibited. 11. Tack welding shall be removed. 12. Welds shall not be started or stopped within 12 inches (300 mm) of a weld junction. 13. Welding leads shall not be clamped so as to cause arc strikes inside RTJ grooves. 14. Grounds may be clamped to hubs, etc. Bolt-on or swivel grounds shall be used whenever possible. 15. ASME B31.3 shall be the authority for welding piping outside the limits of the ASME Pressure Vessel Code. 16. All structural welding shall conform to sizes of welds as noted on drawings or, if not specified, shall conform to the requirements of AWS D1.1. 17. For vessels in cyclic service, as specified in the data sheet, e.g., molecular sieve dehydrators, all attachment welds to pressure parts shall be ground to a smooth radius. 6.5 Heat Treatment and Stress Relieving 1. Postweld heat treatment (stress-relief) shall be provided in accordance with ASME Code, and as specified in the Technical Requirements or vessel data sheet. Vessels subject to sulfide stress cracking (see Appendix VI) shall be postweld heat treated. 2. When heat treatment is required, the whole vessel shall be heat treated at one heating. 3. Flange faces shall be protected against oxidation during heat treatment. 4. Welding shall not be allowed on pressure vessels after stress relieving, unless specifically authorized in writing by Company and in accordance with ASME Code requirements. 5. When heat treatment is required on vessels and equipment where access to the internal surfaces is impossible after the final weld closure, the Supplier shall state in his proposal the method to be used to control scale formation or to remove scale. 6. During postweld heat treatment, vessels shall be blocked and supported as necessary to avoid any deformation or damage. 7. If internal parts are installed in the vessel prior to postweld heat treatment, all parts shall be realigned after postweld heat treatment to comply with the vessel drawing. 8. After postweld heat treatment, warpage shall be corrected and all bolts shall be retightened. 7.0 INSPECTION AND TESTING 7.1 General 1. Company reserves the right to inspect, or for an authorized representative to inspect, vessels at any time during fabrication and to have access to all test records and results. 2. Contractor shall afford Company, free of cost, all necessary and reasonable information and use of facilities needed for determining that vessels are being furnished in accordance with the Technical Requirements and vessel data sheets. 3. Company inspection shall not relieve Contractor of responsibility for all examinations necessary to assure compliance with the ASME Code and the requirements of this specification and the vessel data sheet. 4. Prior to the final inspection, all slag, loose scale, dirt, grit, weld splatter, paint, oil, test medium and other foreign matter shall be removed from inside and outside the vessel. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 23 of 48 General Specification for Pressure Vessels PVM-SU-8.00 5. For vessels in cyclic service, for which attachment welds to pressure parts have been ground to a smooth radius, the ground welds shall be checked by magnetic particle or dye penetrant examination. 7.2 Non Destructive Examination 1. Fabricator shall provide ultrasonic or magnetic particle inspection of all welds utilizing the Flux Core Arc Welding (FCAW) process. 2. For nozzle attachment welds using FCAW, 100% ultrasonic inspection is required. NOTE: Supplemental inspection requirements may be adopted to monitor in-service H2S-induced cracking. 3. Ultrasonic inspection in accordance with ASME Code, Appendix 12 shall be required for all Code Category C and D welds. 7.3 Radiographic Inspection 1. As a minimum, all butt welds (including butt welds for flange-to-pipe nozzles and nozzles constructed of rolled plate) shall be spot radiographed in accordance with ASME Code. a. One radiograph shall be taken showing not less than 14" (350 mm) of weld for each longitudinal and each circumferential joint in the shell and heads. b. One spot radiograph (14") (350 mm) shall be taken of each butt weld in the skirt of a vertical vessel. 2. When 100% radiography is specified, all butt welds shall be included. a. Spot radiography per Section 7.3 item 1 is also mandatory for all Category B welds, including nozzles, only when full radiography is required b. Category C and D welds shall receive the following inspections: 1. Backgouged surfaces of all Category C and D welds shall be liquid penetrant or magnetic particle tested per Appendix 8 or Appendix 6 of the ASME Code, as applicable. 2. All surfaces of completed Category C and D welds shall be magnetic particle inspected per Appendix 6 of ASME Code. 3. Unless otherwise specified, NDE in items 1 and 2, above, will be randomly inspected by a Company inspector or representative. c. When specified in the vessel data sheet as an alternative to Section 7.3 item 2, ultrasonic testing (UT) is required for Category C and D welds in accordance with Code Appendix 12. This option is required only when full radiography is mandated in the vessel data sheet or Project Technical Requirements. 3. When full (100%) radiography is specified for solely Code Category A weld joints, spot radiography shall be required for all Code Category B welds, including nozzles. 4. Welds subjected to forming operations, as might occur in a welded head, shall be fully (100%) radiographed after forming, but before attachment to the vessel. 5. Company shall be notified five (5) working days in advance of final spot radiography, so that Company may designate the locations of the random radiographs. a. For any rejectable weld defects that, in the opinion of Company, do not appear to be random in nature, the entire length of that weld shall be radiographed. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 24 of 48 General Specification for Pressure Vessels PVM-SU-8.00 b. Should additional repairs be required, then Contractor shall repair all defects in accordance with ASME Code, and Contractor shall bear all costs for the additional radiographs and repairs. c. Should repairs not be required, Company will reimburse Contractor for the costs of the additional radiographs. d. Any vessel that becomes fully (100%) radiographed shall be given ASME Code status and stamped as a fully radiographed vessel. 6. For carbon steel vessels, radiographs shall not be taken within 24 hours of completion of the weld being examined. 7. Radiographic film shall be retained by Contractor for at least a year after the date that the Authorized Inspector approves the Manufacturer's Code Data Report. 8. All welds in piping outside the limits of the ASME Code shall be inspected radiographically and interpreted in accordance with ASME B31.3. 9. Piping requiring stress relieving shall be radiographed before and after stress relieving. 7.4 Hydrostatic Pressure Testing 1. After completion of all fabrication, welding, visual inspection, NDE, radiography, stress relieving and telltale-hole air tests, Contractor shall perform a hydrostatic test in accordance with the ASME Code. See Section 7.4 item 8 for hydrostatic test pressure. a. Hydrostatic tests shall be performed in the presence of, and with the approval of, Contractor's Authorized Inspector and/or Company. b. Vessels shall not have been previously hydrotested by Contractor without Company authorization. c. Hydrostatic testing of piping outside the limits of the ASME Code shall be as prescribed in ASME B31.3. 2. Contractor shall furnish all test facilities, equipment and materials, including chart recorder, gages, blinds, studs, nuts, gaskets, etc. necessary for the test. 3. The vessel shall be cleaned internally and externally of all dirt, debris, weld slag, weld spatter, etc. before hydrostatic testing. 4. The hydrostatic test shall be performed with the "in service" type of gaskets, and shall not utilize any gasket sealing compounds. 5. Vessels shall not have been primed, painted, or internally coated prior to hydrostatic testing. 6. Contractor shall provide ten (10) days advance notification so that the hydrostatic test may be witnessed by Company. 7. Fresh potable water shall be utilized for hydrostatic testing. The minimum water and metal temperature for the test shall be 60F (15C) or 30F (17C) above MDMT at MAWP, whichever is warmer. 8. Hydrostatic Test Pressure shall be determined as follows: a. The hydrostatic test pressure shall be the pressure calculated to stress the full thickness, including corrosion allowance and cladding, if any, of the strongest Category A weld to a minimum of the appropriate Code test factor (i.e., 1.3 for Division 1 vessels or 1.25 for Division 2 vessels) times the allowable stress for the material at the test temperature. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 25 of 48 General Specification for Pressure Vessels PVM-SU-8.00 b. This pressure is based on the Code test factor times the Maximum Allowable Pressure New and Cold (MAP). c. No component of the vessel shall be stressed above 90% of its specified minimum yield strength. d. If the hydrostatic test pressure so calculated will stress components of the vessel above 90% of the specified minimum yield strength, the test pressure shall be reduced by the least amount necessary to avoid overstressing weaker components. 9. The minimum test time shall be one (1) hour after stabilization of pressure and temperature. a. Test pressure and temperature shall be chart recorded. b. Ambient air temperature shall be recorded at the start and end of testing. 10. After the final hydrostatic test, the vessel shall be drained completely and dried thoroughly. a. Draining and drying shall be completed within one week of filling the vessel with hydrostatic test water. b. If the vessel cannot be visually inspected to ensure complete drying, the Fabricator shall use a dehumidified air dryer to show that the outlet relative humidity is the same as the inlet relative humidity. 11. Horizontal vessels shall be hydrostatically tested with the permanent support saddles. Additional temporary supports shall not be allowed. 12. Vertical vessels shall be properly supported if hydrostatically tested in the horizontal position. 13. Blinded nozzles, handholes and manways shall be provided with new gaskets after completion of hydrostatic testing and painting. 7.5 Pneumatic Pressure Testing 1. Pneumatic pressure testing shall not be accepted in lieu of hydrostatic testing on vessels. 2. All reinforcing, saddle and wear pads shall be pneumatically tested with air and soapsuds at 15 psig (1 bar) prior to hydrostatic testing. 8.0 PROTECTIVE COATINGS 1. Contractor shall provide external and internal coatings as specified. 2. Coating procedures, including pre-cleaning, surface preparation, application and products to be used shall be reviewed and approved by Company prior to the start of the coating process. 3. The proposed procedures shall be in accordance with the requirements listed in vessel data sheet and the (coating) product data sheets. 4. All coating work shall be performed after completion of all fabrication and testing, including hydrostatic pressure testing and reinforcing pad air testing. 5. The entire vessel (including the inside of the skirt, outside of the bottom head, entire base ring, and all skirt attachments) shall be coated. a. Nozzles shall be painted on the flange edges, inside bolt holes, and up to the gasket surface. b. RTJ flange grooves shall be protected during blasting and greased during painting operations. 6. Couplings shall be tightly plugged with hex-head plugs during blasting and painting. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 26 of 48 General Specification for Pressure Vessels PVM-SU-8.00 7. Bolt holes in vessel supports and attachments shall be blasted and fully primed before assembly. 8. Ladders, cages, platforms and handrails shall be hot-dip galvanized and/or coated. 9.0 IDENTIFICATION AND MARKINGS 1. Vessels shall be provided with a stainless steel nameplate in accordance with the ASME Code. 2. The nameplate shall include the following data as a minimum, which shall be engraved or stamped into the nameplate: a. ASME Code Stamp (indicating degree of radiography and stress relief) b. National Board Registration Number c. Manufacturer's Name d. Manufacturer's Serial Number e. Year Built f. Maximum Allowable Working Pressure - Hot and Corroded (MAWP) g. Maximum Allowable Pressure - New and Cold (MAP) h. Corrosion Allowance i. Shell Material and Thickness j. Head Material, Thickness and Type k. Vessel Name (Service) and Tag Number l. Purchase Order Number m. Vessel Weights - Dry, Operating and Hydrostatic Test n. MDMT at MAWP. o. Lowest allowable MDMT and coincident maximum pressure. 3. Nameplates shall be located so that they are easily accessible after installation. 4. On insulated vessels, the nameplate shall be installed on a "T" or "U" bracket so as not to be covered or obstructed by insulation. 5. Nameplates shall be securely attached to pressure vessels using one of the following methods: a. Seal-welding to shell or head prior to stress relief or hydrostatic testing. b. Riveted (stainless steel) to a “T” or “U” bracket. c. Bolted (stainless steel) to a “T” or “U” bracket with the nuts tack welded. 6. The vessel name (service) and tag number shall be painted or stenciled the on opposite sides of the vessel. a. Lettering shall be black, 6" (150 mm) high capital block letters, and located on the shell horizontal centerline for horizontal vessels, and about 6'-0" (1.85 m) above the base plate for vertical vessels. b. Horizontal vessels longer than 20'-0" (6 m) T/T, or greater than 8'-0" (2.5 m) in outside diameter shall also include identification lettering on both heads. c. Tall vertical vessels shall include additional identification lettering at each operating level as specified by Company. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 27 of 48 General Specification for Pressure Vessels PVM-SU-8.00 7. Contractor shall mark actual vessel dry weight on the shell and heads with paint sticks before shipping. 8. For vessels with internal coating or postweld heat treating, a warning shall be painted on the outside of the vessel after completion stating: “This vessel is internally coated - depressure with care” and/or “This vessel has been postweld heat treated - no welding to this vessel is allowed.” 10.0 PREPARATION FOR SHIPMENT AND STORAGE 1. Contractor shall be responsible for preparing vessels for shipment and storage in accordance with the Commercial Terms and Conditions. 2. After fabrication, ladders, platforms, and other removable items supplied by vessel fabricator shall be completely installed on the vessel in the shop to ensure proper fit-up, then disassembled and shipped separately. a. Each platform and ladder section shall be identified with a metal tag, loosely wired to each section. b. Loose shipped items shall be properly tagged with the item name, the vessel name, and the tag number. 3. All unpainted finished surfaces, e.g., flange gasket faces, threads, etc., shall be coated with suitable rust preventive or grease. a. All bolting shall be lubricated with thread lubricant prior to final installation. b. Telltale holes in reinforcing and saddle pads shall be plugged with heavy grease. 4. All flanged openings shall be protected with a flange cover, plastic sheet, and gasket. a. Flange covers shall be constructed from exterior grade plywood, 1/2" (13 mm) minimum thickness, and secured with a minimum of 50%, or four (4) bolts, whichever is greater. b. A plastic sheet shall be inserted between the flange face and the wooden cover. c. Threaded openings and couplings, except telltale holes in reinforcing pads and saddles, shall be protected with a forged steel hex head pipe plug rated for the maximum allowable working pressure of the vessel. d. Plugs shall be either chromated/cadmium plated carbon steel or 316 stainless steel. 5. Contractor shall provide suitable supports for internal parts, which might be damaged during shipment. a. Temporary internal supports shall be painted yellow, and the vessel shall be clearly identified or tagged as having temporary internal supports. b. If removal of the supports is required prior to putting the vessel into service, the Company shall be notified in writing, with a drawing showing the supports to be removed. 6. Fabricator will submit for review and approval by Company, a written storage procedure for storage up to twelve (12) months. 7. All gage glasses and cocks shall be tagged, packed in clearly marked waterproof crates suitable for twelve (12) months' outdoor storage, and shipped separately. 8. Contractor shall be responsible for loading and securing vessels on transport truck/vessel at Contractor's manufacturing facility. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 28 of 48 General Specification for Pressure Vessels PVM-SU-8.00 a. The Contractor shall provide the vessel with wood skids or crates to ensure protection against damage during shipment. b. Contractor shall provide Company at least one (1) week advance notice of vessel completion and delivery availability. 9. If vessel is specified to be stored, Contractor shall provide suitable type and quantity of desiccant for the stated storage period. 10. Desiccant shall be placed in bags and tagged for ease of identification, removal and replacement. 11. Contractor shall notify Company in writing of any special handling procedures, such as: a. Limitations on lifting or sling angles. b. Restrictions on laying vertical vessels in the horizontal position. c. Internal supports necessary for shipment. d. Height restrictions, e.g., bridges, power lines, etc. along land transportation routes of the completed vessel(s). 12. Each removable piece of equipment that will be shipped separately from the vessel shall be identified with a stainless steel tag. a. The tag shall be securely wired to the equipment. b. The identification tag shall be die stamped with the item number, platform number, piece number, and the total number of pieces. 13. The identification tag shall include the vessel tag name and number, to which each piece corresponds. 14. One full-sized copy of the approved vessel as-built drawings shall be sealed in plastic and shipped with the vessel. 15. Fabricator shall clearly mark, in 2-inch (50 mm) letters, the proper information required to identify the items inside crates. 16. A “bill of lading” placed into a waterproof container shall be attached to both the inside and outside of each crate. 17. If Contractor is responsible for shipping, Company shall be notified at least one week in advance of the intended vessel delivery. 11.0 DOCUMENTATION REQUIREMENTS 1. Contractor shall provide documentation in accordance with ASME Code and the vessel data sheet or Technical Requirements. 2. The following approval documentation shall be submitted to Company for review and approval prior to the start of fabrication: a. ASME Code Calculations b. Company Required Calculations - Process and Sizing, Wind, Transportation, Lift, Center of Gravity, etc. c. Weld Map with WPS Identification (including MDMT identifications and welding sequences for critical joints, if requested by Company) d. Weld Procedure Specifications and Procedure Qualification Records August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 29 of 48 General Specification for Pressure Vessels PVM-SU-8.00 e. General Arrangement and Elevation Drawing f. Fabrication Sections and Details g. General Design, Fabrication and Painting Procedures and/or Notes 3. Contractor approval submittals shall include one (1) reproducible and four (4) sets of full size copies or prints. 4. Company reserves the right to relocate the vessel connections, clips, lugs, etc., before fabrication is begun. 5. Contractor shall allow two (2) weeks for Company review and return of approval drawings. 6. Contractor's general arrangement and fabrication drawings shall include the following information as a minimum: a. Plan, Elevation and End Views - fully dimensioned and drawn to scale b. Shell Thickness and Head Thickness and Type c. Details of all Vessel Internals and External Attachments d. Bill of Materials - component, material specs, quantities, ratings, and thickness e. Nozzle Schedule - mark, quantity, description, sizes, rating, type, thickness f. Flange ratings g. Nameplate Details - including dimensions and mounting details h. Vessel Weights - shipping, dry, hydrotest, operating normal and operating flooded (or 100% sand-filled, if applicable) i. Hydrostatic Test Pressure j. Radiography and NDE Requirements k. Weld details l. Surface preparation for coatings: external and internal m. Coating requirements: external and internal n. Clearance from main seams for attachments and penetrations o. Bill of materials 7. After completion of the vessel, Contractor shall provide “Record Data Books” to Company. The Record Data Books shall include the following documentation, as a minimum: a. ASME Code Data Report b. Drawings, Sections and Details (“As-Built”) c. Calculations (ASME Code and Company Required) d. Weld Procedure Specifications, Procedure Qualification Records and Weld/Welder Identification Maps e. Mill Test Certificates f. Fabrication and Inspection Records g. Hydrostatic Test Chart and Certificate h. Stress Relief Chart and Certificate (if applicable) i. Nameplate Rubbing or Photograph August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 30 of 48 General Specification for Pressure Vessels j. PVM-SU-8.00 Operating and Maintenance Manual (if applicable) 8. Contractor shall utilize industry standard drawing practices, as a minimum, in executing the work. a. For instance, all drawings shall utilize title blocks and revision blocks for drawing identification and control. b. All drawings shall be dated and signed by appropriate Contractor representatives. c. When revised, Contractor shall identify revisions on drawings with clouds and revision triangles and the title and revision blocks shall be appropriately completed with descriptions, dates, and signatures. 9. Contractor shall furnish final as-built drawings and data sheets in both hard copy and editable electronic formats. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 31 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX I: BASIC MATERIAL REQUIREMENTS FOR CARBON STEEL VESSELS TABLE 1: BASIC MATERIAL REQUIREMENTS COMPONENT MATERIAL REQUIREMENT NOTES Shell SA-516 1, 4 Heads SA-516 2, 4 Long Weld Neck Flanges SA-105 3 Weld Neck Flanges SA-105 3 Rolled Nozzle Necks SA-516 4, 9 Pipe Nozzle Necks SA-106 Grade B Reinforcing Pads SA-516 Couplings SA-105 NOZZLE ASSEMBLIES 4 PIPING: PRESSURE CONTAINING Pipe SA-106 Grade B Weld Fittings SA-234 Grade WPB Forgings SA-105, SA-181 Class 60 Flange Bolting SA-193-B7 studs w/ SA-1942H nuts 5, 7 Flange Gaskets: Flexitallic style “CG” spiralwound, 304 SS with flexite super filler for ANSI Class 150 through 600, or Company approved equal Raised Face Ring Joint: •ANSI Class 900 •ANSI Class 1500 August 2010 (E) Type “R” Octg. Iron ring, cad. plated, Type “D” Type “RX” Octg. Iron ring, cad. plated, Type “S” 8 © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 32 of 48 General Specification for Pressure Vessels PVM-SU-8.00 TABLE 1: BASIC MATERIAL REQUIREMENTS (CONTINUED) COMPONENT MATERIAL REQUIREMENT NOTES INTERNALS: NON-PRESSURE CONTAINING PARTS Plate and Repads SA-516, SA-285 Grade C Pipe SA-106 Grade B, SA-53 Grade B, API 5L Pipe Fittings SA-105, SA-234 Grade WPB Angle, Channel, Barstock SA-36 Bolting 316 Stainless Steel 4,10 EXTERNAL ATTACHMENTS Lifting Lugs and Re-Pads SA-516 4 Reinforcing Pads/Saddles, Base Rings, Skirt Opening Reinforcements SA-516 4 Angle, Channel, Barstock SA-36 SUPPORTS Horizontal Vessel Saddles SA-283 or SA-285 4, 6, 10 Vertical Vessel Skirts SA-283 or SA-285 Grade C, SA-515, SA-516 4, 6, 10 Vertical Vessel Legs: Angle, Channel, Bars Plate SA-36 SA-36 GAGE VALVES, GAGES Only carbon steel gage valves are acceptable in hydrocarbon service; Daniels or Penberthy. Contractor shall install all gages for inspection by Company to ensure proper fit. Note 1: Vessels 24" O.D. and smaller may utilize SA-106, Grade B seamless pipe for the shell. Note 2: Vessels 24" O.D. and smaller may utilize SA-234 Grade WPB pipe caps in lieu of forged elliptical heads. Note 3: For ANSI Class 150 and 300 flanges, SA-181 Class 60 material may be utilized in lieu of SA-105 if the latter is not available. Note 4: All SA-515 and SA-516 components shall be of the same grade material. Note 5: Bolting shall be continuous-thread alloy steel bolt studs according to ASME SA-193 Grade B7 and semi-finished hex nuts according to ASME SA-194 Grade 2H. Studs and nuts shall have Class II fit. All threads shall be according to ASME B1.1: Coarse Thread series 7/8" and smaller, 8 pitch thread series 1" and larger. All studs and nuts are to be chromated/cadmium plated or have Xylan/Teflon August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 33 of 48 General Specification for Pressure Vessels PVM-SU-8.00 coating, Fluro-Kote #1, blue (Metal Coatings Corporation, P.O. Box 630407, Houston, Texas 77306) or Company approved equal. For studs in blind holes, either the end of the stud or the bottom of the hole shall be relieved to prevent galling. Note 6: Vessel supports constructed of SA-283-C materials shall be limited to a maximum thickness 5/8" and a minimum temperature of 32°F (0C). Note 7: Flange bolting for sour service vessels shall be SA-193-B7M studs and SA-194-2HM nuts per NACE MR-01-75. The additional requirements of Note 5 apply. Note 8: (1) ANSI Class 1500 flange gaskets for sweet services shall be Type “R” Octagonal iron ring, chromated/cadmium plated, Type “S”. (2) ANSI Class 1500 flange gaskets for sour services shall be Type “RX” Octagonal ring, annealed Type S310. (3) ANSI Class 2500 flange gaskets for sour services shall be Type “RX” Octagonal ring, annealed Type S316. Note 9: Rolled plate used for nozzles shall be the same as vessel shell or head material in which the nozzle is to be installed. Note 10: The following grades of material are assigned as exceptions/additions to Curve A in Code Figure UCS-66: Plate Curve A SA-285 above 3/4-inch thick SA-515 above 3/4-inch thick August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 34 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX II: ADDITIONAL REQUIREMENTS FOR ASME PRESSURE VESSELS WITH THICKNESS GREATER THAN 1.5 INCHES (38 MM) II.1 SCOPE Pressure vessels with thickness greater than 1.5" (38 mm) shall comply with the additional requirements specified herein, which shall apply to carbon steel, clad carbon steel, and stainless steel materials. The appropriate ASME Section VIII, Division 2 paragraphs shall be substituted for ASME Section VIII, Division 1 referenced paragraphs, e.g., AM-204 through 218 for UCS-66 and 67. II.2 MATERIALS 1. All forgings shall be forged as close as practicable to finished shape and size to develop metal flow in a direction most favorable for resisting the stresses encountered in service. 2. The tensile and Charpy V-notch impact tests required for certification of all plate, forging, and pipe grades of material according to Paragraph AF-101 shall represent the vessel in the completed condition. a. Compliance with this requirement shall be verified by subjecting specimens for tensile and Charpy V-notch impact tests to the same complete thermal history that will be required for fabrication of the vessel. b. The thermal history shall include all hot forming and heat treatment steps, plus at least 2 additional postweld heat treatment cycles to allow for shop or field repairs. 3. For cold-formed components, stress relief heat treatment shall be required if fiber elongation is between 5% and 10%. a. Complete re-heat treatment in accordance with the Code (SA) material specification shall be required if fiber elongation exceeds 10%. b. Cold sizing shall be permitted after stress relief heat treatment, if necessary to correct distortion, providing the fiber elongation does not exceed 5%. 4. For hot formed components, complete re-heat treatment in accordance with the Code (SA) material specification shall be required if the temperature of hot forming exceeds the normalizing temperature for normalized material, or the tempering temperature for normalized and tempered or quenched and tempered material. II.3 DESIGN 1. Code Category C flange welds shall not be allowed, unless specifically approved in writing by Company. 2. On vessels with a shell thickness of 2" (50 mm) and greater, all nozzles, manways, and other shell openings shall be integrally reinforced type with full penetration welds. 3. Vessels in cyclic service shall have nozzles that are fully radiographable per ASME Code. II.4 WELDING 1. When Charpy V-notch impact tests are required, welding current and travel speed shall be considered essential variables for welding procedure qualification, to assure that production welds achieve substantially equivalent impact properties as the qualification welds. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 35 of 48 General Specification for Pressure Vessels PVM-SU-8.00 2. Production test plates in accordance with Paragraph AT-203 shall be required for each vessel when Charpy V-notch impact tests are required. a. Production test plates shall be subjected to the same total thermal history as the finished vessel. b. Charpy V-notch impact tests shall be made for the base metal, weld metal, and heat affected zone. 3. Postweld heat treatment shall meet or exceed the minimum temperature and the minimum time required by AF-402. Company shall not accept utilization of Code Table AF-402.2 for applying the postweld heat treatment at a lower temperature for an increased length of time. 4. Postweld heat treatment of the completed vessel as a whole shall be preferred. a. With written approval from Company, local heat treatment shall be permitted only for Code Category B girth welds. b. The locally heated band shall not include any nozzles. 5. A sufficient number of thermocouples shall be attached to the vessel during postweld heat treatment, and recorders shall be used, to verify that the required temperature and holding time have been obtained. 6. The temperature difference between any two thermocouples shall not exceed 250F (120C) at any time, especially during the heating and cooling cycles. II.5 INSPECTION 1. All forging surfaces, regardless of thickness, shall be magnetic particle inspected in accordance with the requirements of Appendix 9, Article 9-1, after final machining. 2. All Code Category A and B welds, including nozzles, shall be fully (100%) radiographed after postweld heat treatment. When approved by Company, radiography may be performed before postweld heat treatment if ultrasonic inspection is performed after postweld heat treatment. 3. All Code Category D nozzle welds shall be fully (100%) ultrasonically tested after postweld heat treatment. 4. Pressure retaining plate material shall be ultrasonically examined by straight-beam method in accordance with ASTM SA578 Level B. 5. Plate edges, including weld bevel preparation, shall be examined for laminar-type discontinuities using magnetic particle or liquid penetrant method. 6. All weld pad buildups for attachment of internal or external components and supports shall be ultrasonically tested. 7. When possible by design, all skirt-to-vessel welds shall be ultrasonically tested. Skirt-to-vessel welds that cannot be ultrasonically tested shall be magnetic particle tested after the root pass is completed and every third layer thereafter. A dry-powder technique shall be acceptable. 8. After the removal of temporary attachments and surface grinding of the attachment welds, all ground surfaces shall be magnetic particle tested. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 36 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX III: ADDITIONAL REQUIREMENTS FOR STAINLESS STEEL PRESSURE VESSELS III.1 MATERIALS 1. Stainless steel heads and transition sections which have been cold formed shall be solution annealed and then cold sized to correct for distortion, if any, prior to welding to the shell. 2. Stainless steel materials with strength enhanced by cold work shall not be allowed. Stainless steel bolts shall have machined heads and threads; rolled threads shall not be acceptable III.2 DESIGN The allowable design stress for stainless steel vessels shall not exceed two-thirds (2/3) of the yield strength at the design temperature, unless a higher allowable design stress is approved in writing by Company. III.3 WELDING 1. When post-weld heat treatment is specified for stainless steel vessels, all welds and cold formed parts shall be thermally stress relieved at 1550°F (843C) to 1600°F (871C) for one (1) hour per inch of thickness, with a one (1) hour minimum, and then properly air cooled. 2. Chemical analysis shall be performed on deposited weld metal for each lot of stainless steel welding consumables. a. This shall be performed either on test plates, or from sample drillings of production welds. b. Analysis shall meet the requirements of ASME SFA 5.4 of the grade of stainless steel specified. 3. Stainless steel base metal and weld metal shall be cleaned so as to provide the maximum corrosion resistance. 4. Contractor shall provide, prior to the start of fabrication, the proposed cleaning procedure to Company for review and approval. III.4 INSPECTION 1. The ferrite content of all Code Category A, B, C, and D stainless steel weld joints shall be determined on both surfaces of each finished weld before any post-weld heat treatment. 2. Ferrite content shall be determined using a magnetic instrument calibrated according to AWS A4.2 standard procedure, and shall be between 3FN and 10FN. 3. All ferrite measurements shall be recorded, along with the accurate location of each measurement. III.4 HYDROSTATIC PRESSURE TESTING Test fluid for solid austenitic stainless steel or cladded vessels shall not contain more than 100 ppm chloride content. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 37 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX IV: ADDITIONAL REQUIREMENTS FOR STAINLESS STEEL CLAD PRESSURE VESSELS IV.1 SCOPE This Appendix gives additional requirements for the design and fabrication of clad pressure vessels. IV.2 DESIGN 1. Pressure Design Thickness of the stainless steel cladding or weld overlay shall not be included in the pressure design, unless specifically approved by the Company in writing. 2. Solid Stainless Steel Components Solid stainless steel materials shall not be used for pressure-containing parts, unless specifically detailed on the Company vessel drawing or specifically approved by the Company in writing. 3. Openings a. For clad vessels with a shell thickness less than 2" (50 mm), nozzles and manways shall conform to Standard Drawing GD-C99663, Details D, E, or F. Stainless steel bosses according to Detail G are permitted only when specifically detailed on the vessel drawing. b. For clad or weld overlaid vessels with a shell thickness of 2" (50 mm) or greater, nozzles and manways shall be lined or clad in accordance with Standard Drawing GF-C1030. 4. Supports a. Supports for heavy loads, such as rings supporting beams or catalyst support grids, shall be constructed of the same material as the vessel base metal. 1. Supports shall be welded to the vessel's wall base metal and overlaid with the same alloy as used on the vessel wall. 2. An alternate design is a weld build-up support of the same metallurgy as base metal and overlaid with same alloy as vessel overlay. b. Light internal attachments may be welded directly to the cladding. Refer to the ASME Code, Section VIII, Div. 2, AD-900(c) (3). IV.3 MATERIALS 1. Base Material Base materials shall be furnished to the requirements of Appendix I. 2. Cladding Processes a. Roll clad plate shall be used for thickness of 4" (100 mm) or less. b. Weld overlay cladding shall be used for thicknesses over 4" (100 mm). c. Explosion bonded clad material may be used only with the written approval of the Company. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 38 of 48 General Specification for Pressure Vessels PVM-SU-8.00 3. Cladding Thickness a. Unless specified otherwise by Company, the minimum allowable thickness of cladding shall be 1/8" (3 mm). b. Without specific written Company approval, cladding thickness shall not exceed 3/8" (10 mm). 4. Explosion Bonded Clad Plate a. When approved for use, all explosion bonded clad plate and forgings shall be ultrasonically examined to verify bond. Examination method shall be in accordance with ASTM Specification SA-435. b. In addition to the acceptance standards of Paragraph 6 of SA-435, two or more defects smaller than described in Paragraph 6.1 shall be unacceptable unless separated by a minimum distance equal to the greatest dimension of the larger defect, or unless they may be collectively encompassed by the circle described in Paragraph 6.1. c. Certification of tests shall be furnished to Company. 5. Weld Overlay Cladding a. Overlay shall consist of a first pass of 309L alloy with a subsequent pass (or passes) of specified stainless steel. b. A single pass procedure, whereby the filler metal/base metal mix results in an equivalent analysis for the specified minimum thickness, will be considered provided the fabricator can demonstrate the reliability of the proposed procedure and freedom from interface microcracking. 6. General Requirements for Roll Bonded and Explosion Bonded Clad Plate a. Austenitic chromium-nickel stainless steel cladding shall either meet the extra low carbon (0.03% maximum) specification, or shall be a grade stabilized with columbium or titanium, whichever is specified by Company. b. Check analysis for carbon content only shall be furnished for extra low carbon grades of austenitic stainless steels, cladding or solid, in accordance with the applicable ASME Code requirements and the following additional requirements: 1. Check analysis shall be required only for alloy pressure containing parts such as nozzles and bosses and for cladding in contact with the contents of the vessel. 2. When check analysis is required for cladding material, it shall be required for each individual clad plate in contact with the contents of the vessel. c. Clad plate shall comply with the requirements of ASTM SA-263 or SA-264. d. Austenitic stainless steel clad plates shall be normalized by heating to between 1675F (913C) and 1725F (941C) for one hour per inch of thickness, followed by air cooling. e. Average grain size of the base material, per ASTM E112, shall be no. 5 or finer in normalized plate, as supplied by the mill. f. Except where prohibited by the ASME Code material specifications, an air blast shall be used to cool plates greater than 1-1/2" (38 mm) thick through the temperature range in which carbide precipitation occurs. g. After normalizing, plate shall be tempered as necessary for fabrication. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 39 of 48 General Specification for Pressure Vessels PVM-SU-8.00 h. After cold forming (below 1200F) (649C) of clad heads, toriconical transition sections or similar parts, stress relief shall be performed. 1. If such parts are hot formed between 1600F (871C) and 1750F (954C), they shall be tempered. 2. If forming operations are conducted at an initial heating temperature between 1200F (649C) and 1600F (871C), or above 1750F (954C), the parts shall be normalized. All heat treatment shall be performed prior to welding the part to the shell. 3. After such heat treatment, parts may be cold sized, if necessary, to correct for distortion. i. Clad material shall not be quenched after cladding. j. Shear testing shall be required for all clad plates. Testing procedures and acceptance criteria shall be in accordance with the applicable ASME (SA) Specification. k. Ultrasonic examination according to SA-578 shall be made of all clad plates within 1T (1 x plate thickness) of all edges to be welded, and covering an area extending 1T from all load bearing internal attachments designated on the vessel drawing. l. Cladding shall be removed where any lack of bond is detected. The defective area shall be repaired by weld overlay cladding. (See “IV.5.2 Weld Overlay” item 3.) m. Company shall be notified in writing of any repair exceeding 10 square inches in area, or of any plate requiring more than three repairs regardless of size. n. All repairs, regardless of area, shall be recorded on a scaled sketch. IV.4 WELDING The requirements of this section apply to all austenitic stainless steel weld overlay cladding, including: 1. Weld overlay as the primary method of applying the internal lining, 2. Weld overlay of groove welds in roll clad or weld overlay clad base materials, and 3. Repair areas of roll clad or explosion bonded clad plate. IV.4.1 General 1. After each welding pass, the weld shall be cleaned of all flux and slag by power wire brushing, grinding, or hand tools. a. Only stainless steel wire brushes shall be used. b. Slag picks and hammers shall be tipped with austenitic stainless steel or stellite. 2. Argon and argon/helium gas mixtures are required for processes that require shielding. 3. Additions of hydrogen, oxygen, or carbon dioxide to the shielding gas are not permitted. 4. Details of the weld overlay cladding procedure (WPS), including process, wire, flux, and number of layers, shall be established by Fabricator for approval by Company before procedure qualification. IV.4.2 Welding Procedures and Qualifications 1. 1.Procedure qualifications shall be made using the specified base material and the same type and brand of flux and weld wire to be used in production overlay cladding. 2. Welding current and travel speed shall be considered essential variables. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 40 of 48 General Specification for Pressure Vessels PVM-SU-8.00 3. Weld overlay cladding procedures shall be qualified in accordance with ASME Code Paragraph UCL-40 and ASME Code Section IX. 4. The samples of overlay and backing shall be subjected to heat treatment simulating that of the final vessel including intermediate stress relief heat treatments, if used. 5. After heat treatment, cladding on the weld overlay procedure qualification test plate shall be examined by liquid penetrants in accordance with Code Division 1, Appendix 8, or Code Division 2, Appendix 2, Article 9-2, whichever is applicable. 6. After heat treatment, side bend specimens shall be machined from the samples. a. The specimen width shall be twice the thickness of the overlay. b. Specimens shall contain the entire overlay, the bond line, and a thickness of base metal equal to the thickness of the overlay. c. The length of the specimen shall be 1-1/2" (38 mm) minimum, and the width of the bend specimen in the direction of bending shall be 1/8" (3 mm). d. The finish machined specimens shall be bent 180 degrees around a 1/2" (12.5 mm) pin with the “neutral axis” of the bend specimen perpendicular to the bond area. e. After bending, the specimens shall have no cracks or open defects exceeding 1/16" (1.5 mm) measured in any direction on the convex surface, except that cracks occurring on the corners of the specimens during testing shall not be considered rejectable unless there is definite evidence that they result from slag inclusions or other internal defects. 7. The ferrite content of the deposited weld metal shall be determined on overlay weld procedure qualification plates and shall be between 3% and 10%, as determined by the Schaeffler diagram. 8. The qualification test plate shall be checked to ensure that the required composition is achieved. a. Samples shall be taken from the surface and from the top of the specified minimum allowable thickness of cladding. b. The specimens shall be milled and shall each represent a total thickness not greater than 1/32" (0.8 mm). 9. The composition of each specimen shall meet the composition requirements set forth in ASME Code Specification SFA-5.4 for the grade of stainless steel specified for the second pass of the overlay. 10. All weld repair procedures shall be qualified in accordance with ASME Code Paragraph UCL-40 and ASME Code Section IX and shall conform to the additional requirements set forth above for the weld cladding procedures. IV.4.3 Production Welding 1. Weld overlay cladding shall be applied to base metal which has been grit blasted to a Steel Structures Painting Council SSPC SP-10 “near white” finish (a SSPC SP-5 “white metal” finish is required for processes that do no use a flux, such as GTAW). 2. Weld overlay cladding shall be applied after normalizing, but before postweld heat treatment. 3. Weld overlay cladding shall be applied after heat treatment of the base metal with the exception of the postweld heat treatment. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 41 of 48 General Specification for Pressure Vessels PVM-SU-8.00 4. Weld overlay cladding shall be applied circumferentially. For long or small nozzles where it is impractical to apply the weld overlay circumferentially, it may be applied longitudinally, with Company approval. 5. The finished weld overlay deposit shall have the minimum thickness of undiluted, stainless steel material indicated on the drawings. 6. The maximum total cladding thickness shall not exceed 3/8" without specific, written Company approval. 7. The composition of the finished weld overlay deposit from the surface to the specified minimum overlay depth shall conform to the requirements set forth in ASME Specification SFA5.4 for the grade of stainless steel specified on the drawings. 8. For austenitic stainless steel weld overlay, the composition of the finished weld overlay deposit from the surface to the specified minimum overlay depth shall conform to ASME Specification SFA-5.9 for 316L stainless steel, with the exception that the minimum molybdenum content shall be 1.5%. 9. The ferrite content of the deposited weld metal shall be between 3 and 10FN as determined by a magnetic instrument calibrated according to AWS A4.2 standard procedure. Ferrite content is to be measured prior to any heat treatment. 10. Internal attachments welded to the cladding shall be welded with E309L after final PWHT. Low heat input multipass welding with small diameter welding rods shall be used. IV.5 INSPECTION IV.5.1 Pressure-containing Welds 1. At the last stage of fabrication prior to applying the overlay, a magnetic particle examination shall be made of the surfaces of all Category A, B, C, and D welds that are to be covered by weld overlay cladding. 2. All required radiographic and ultrasonic examinations shall be performed on completed weld joints after the weld overlay cladding has been applied. IV.5.2 Weld Overlay 1. The composition of the top layer of the weld overlay shall be checked for Cr, Ni, Mo, Cb, and C contents as follows: a. Two locations for each cylindrical shell course and head. b. One location for each nozzle, and for each Category A, B, and D weld seam. c. The content of each specified element shall be determined by spectrographic analysis. Portable nondestructive instruments may be used, but the procedures must be submitted to the Company for approval. d. When it is necessary to remove a sample from the overlay to make the analysis, the sample shall be 1/16" (1.5 mm) thick measured from the top surface. e. If the composition does not conform to the requirements of “IV.4.3 Production Welding”, item 7, the extent of the nonconformity shall be determined by additional chemical analyses, and all nonconforming weld overlay shall be removed. 2. The ferrite content of the top layer of weld overlay shall be determined before postweld heat treatment by a magnetic instrument according to the requirements of “IV.4.3 Production Welding” item 9 as follows: August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 42 of 48 General Specification for Pressure Vessels PVM-SU-8.00 a. Ten locations per shell course, selected at random. b. Ten locations on each vessel head, selected at random. c. One location per foot of circumference at both ends of nozzles and manways. d. One location at each Category A, B, C, and D weld. e. If the ferrite content does not conform to the requirements of “IV.4.3 Production Welding” item 9, the extent of nonconformity shall be determined by additional ferrite measurements, and all nonconforming weld overlay shall be removed. 3. The completed weld overlay shall be checked for bond flaw indications, after postweld heat treatment, by ultrasonic examination in accordance with ASTM SA-578. a. If indications of flaws are detected, the size of the flaws shall be determined by additional ultrasonic examination. b. Flaws that exceed acceptance level S6 shall be removed. c. Unless indicated otherwise in the vessel data sheet, the coverage of the ultrasonic examination shall be: 1. One location per lineal foot along the vessel length. 2. One location per foot along a meridian of each vessel head. 3. One location per foot of circumference at both ends of nozzles and manways. 4. One location per foot of length of Category A, B, and D weld seams. d. When indicated in the vessel data sheet, the coverage of the ultrasonic examination shall be: 1. One location per linear foot along the vessel length in each of four quadrants. 2. One location per foot along a meridian of each vessel head in each of four quadrants. 3. One location per foot of circumference at both ends of nozzles and manways. 4. One location per foot of length of Category A, B, and D welds. 4. The entire surface of all weld overlay cladding shall be sufficiently smooth and clean to permit liquid penetrant examination for fissures and cracks. a. Liquid penetrant examination of the entire surface shall be performed in accordance with Appendix 8 of ASME Code, Section VIII, Division 1. b. All relevant indications of surface fissures and cracks shall be removed. 5. All ground areas shall be subject to 100% liquid penetrant examination to ensure that the defect has been removed. 6. All repairs of weld overlay shall comply with all of the requirements of “IV.4 Welding” and “IV.5 Inspection”. IV.6 HYDROSTATIC TEST 1. The hydrostatic test of the completed vessel shall be conducted according to Section 7.4. 2. The cladding thickness shall be included in the calculation of the required stress level. 3. The chloride content of hydrotest water shall not exceed 100 ppm. 4. Chemical analysis or certification from water supplier (not older than 30 days) is required. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 43 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX V: MARINE SYSTEM PRESSURE VESSEL REQUIREMENTS V.1 SCOPE 1. When designated on the pressure vessel data sheet as a MARINE SYSTEM pressure vessel, such pressure vessels will also be required to meet the requirements as described in 46 CFR Part 54. 2. Part 54 requires that pressure vessels be designed, constructed and inspected in accordance with ASME VIII, Division 1 except as limited, modified, or replaced by specific requirements in 46 CFR Part 54. 3. The requirements listed in 46 CFR Part 54 vary depending on the design conditions of the pressure vessel, primarily service, pressure, and temperature. a. The most common conditions for offshore facility applications under USCG jurisdiction are described in this Appendix. b. For requirements of other MARINE SYSTEM pressure vessels, refer to Part 54 in its entirety. c. Section “V.2 PRESSURE VESSEL TYPES” below describes the design conditions covered by this Appendix. 4. Should there be a conflict between this and other pressure vessel specifications, the ASME Code and/or this Appendix, the more stringent shall apply. Company shall be notified of all conflicts. V.2 PRESSURE VESSEL TYPES 1. To delineate the applicability of various sections of the USCG requirements, this paragraph describes several types of pressure vessels. 2. Refer to 46 CFR Part 54 in its entirety if the pressure vessel design conditions do not fit within the limitations of one of these types. TABLE 2: LIMITATIONS OF CONDITIONS Limitations of Conditions Pressure/Temperature Limits Type USCG Definition A Class II Hazardous Material Gas - 30 to 600 psig from 0 to 700F Liquid - 200 to 600 psig from 0 to 400F Class III Hazardous Material Gas - up to 30 psig from 0 to 275F Liquid - up to 200 psig from 0 to 250F August 2010 (E) Volume Services No limits Diesel or helicopter fuel (classification of other materials as hazardous must be approved by Company and based on USCG definition). © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 44 of 48 General Specification for Pressure Vessels PVM-SU-8.00 TABLE 2: LIMITATIONS OF CONDITIONS(CONTINUED) Limitations of Conditions Type USCG Definition B Class II Non-hazardous Material C Same as Type B Pressure/Temperature Limits Volume Services Gas - 30 to 600 psig from 0 to 700F Liquid - 200 to 600 psig from 0 to 400F Over 5 cu. ft. Air, Seawater, or Freshwater (classification of other materials as non-hazardous must be approved by Company and based on the USCG definition. Same as Type B Equal to or less than 5 cu. ft. Same as Type B V.3 REQUIREMENTS FOR TYPE A AND TYPE B PRESSURE VESSELS V.3.1 Drawings and Plans Contractor shall develop detailed drawings and plans for Company review in accordance with 46 CFR, Subpart 54.01-18 and 54.01-5e. These documents shall be sent to Company for review with the other Contractor data requirements. These plans may need to be submitted to the USCG for review (see V.4 and V.5 below). These plans must be certified by a registered professional engineer as meeting the design requirements of this Specification, this Appendix and the ASME Code. The certification must appear on all drawings and analyses. V.3.2 Pressure Vessel Identification In addition to the identification stamping information listed in Section 9.0 of this Specification, pressure vessel identification shall include the USCG class (see section 2.0 or Table 54.01-5B in 46 CFR Part 54 for the listing of Class). The USCG symbol and number shall be stamped on the pressure vessel by the Marine Inspector, either at the shop for Type A vessels or at the installation location for Type B vessels V.3.3 Reports The Contractor shall complete and certify the data reports required by 46 CFR Subpart 54.10-25. V.4 ADDITIONAL REQUIREMENTS FOR TYPE A VESSELS 1. Type A pressure vessels will require USCG plan approval. The detailed plans developed in accordance with para. V3.1 shall be submitted by Contractor in accordance with 46 CFR Part 50.20. 2. Type A vessels will require USCG shop inspection and stamp by USCG Marine Inspectors as described in 46 CFR Subparts 54.10-3, 54.10-10, and 50.30-20. Contractor shall notify the Officer in Charge of Marine Inspection of the intended fabrication of vessels that will require Coast Guard inspection. • Type A vessels will require hydrostatic testing in accordance with CFR Subpart 54.10-10. • Type A Vessels will be designed and fabricated for MAWP in accordance with 46 CFR Subpart 54.10-5. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 45 of 48 General Specification for Pressure Vessels PVM-SU-8.00 3. Fabrication and welding for Type A vessels shall be in accordance with 46 CFR Subpart 54.20 and 46 CFR Part 57. 4. Type A vessels also require USCG field inspection at the installation site. V5.0 ADDITIONAL REQUIREMENTS FOR TYPE B VESSELS For Type B pressure vessels, the Contractor will not be required to submit the documentation, as described in Section V3.1, to the USCG for approval prior to fabrication. In addition, the USCG does not require a shop inspection, but will perform a field inspection of the vessels and plans. The USCG visual field examination of the vessels and review of the plans will be made prior to installation, according to 46 CFR Subpart 54.10-3c. Following satisfactory USCG field inspection, Type B vessels will receive a USCG stamp. V6.0 REQUIREMENTS FOR TYPE C VESSELS Type C pressure vessels do not have any additional requirements of 46 CFR Part 54. These vessels shall comply with this Specification and the ASME Code. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 46 of 48 General Specification for Pressure Vessels PVM-SU-8.00 APPENDIX VI: MATERIALS FOR CARBON STEEL PRESSURE VESSEL PARTS SUBJECT TO SULFIDE STRESS CRACKING Vessels in sour service shall meet the requirements of NACE MR-01-75 as well as the additional requirements of this Appendix. VI.1 SHELL AND HEADS 1. Shell and head material for vessels designed for H2S service shall be normalized SA-516-70. The normalizing temperature shall not exceed 1750F (954C). a. The hot forming temperature for normalized material shall not exceed the normalizing temperature unless the material is renormalized after hot forming. b. Cold formed components shall be renormalized. 2. Unspecified elements, i.e., Copper, Nickel, Chromium, Molybdenum, Vanadium, Titanium and Columbium, in SA-516-70 material, shall conform to the limitations of ASTM A20/ A20M Paragraph 7, Table 1. 3. Corrosion allowance on shell and fittings shall be a minimum of 0.125" (3 mm). 4. Plate shall conform to the following chemistry limits: • CEq = 0.43 max. [CEq = C + Mn/6 + (Cu + Ni)/15 + (Cr + Mo + V)/5] • S = 0.002 wt. % max. • P = 0.008 wt. % max. • Nb + V = 0.020 wt.% max. VI.2 SUPPORTS AND MISCELLANEOUS PARTS 1. Vessel supports and non-pressure parts shall be fabricated from material complying with ASTM A285 Grade C as a minimum. 2. ASTM A36 material may be used for structural plates, shapes, and beams. VI.3 FORGINGS Forging material shall be in accordance with ASTM A105 [1-1/2 inch (38 mm) and smaller] or ASTM A234 WPR [2 inches (50 mm) and larger], normalized. VI.4 PIPE Pipe shall be Grade B seamless and in accordance with ASTM A106, normalized. VI.5 FITTINGS Pipe fittings such as weld ells, weld caps, weld reducers, etc., shall be SA-234 Grade B or Company approved equal, normalized. VI.6 COUPLINGS Threaded connections shall not be permitted VI.7 INTERNAL BOLTING Bolting material shall be SA-193-B7M with SA-194-2HM nuts. VI.8 POSTWELD HEAT TREATMENT Vessels in sour service shall be postweld heat treated. August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 47 of 48 General Specification for Pressure Vessels VI.9 PVM-SU-8.00 HARDNESS All carbon steel pressure-containing components, including weld metal and heat affected zones, shall not exceed BHN 200, unless otherwise specified by the component's ASTM material specification. VI.10 WELD PROCEDURE QUALIFICATION 1. Test welds shall be made with the lowest weld heat input that will be used in vessel construction, including fillet attachments. 2. Each weld procedure test shall include two micro-hardness traverses of the weld and weld heat affected zones made on a polished cross section of the weldments. a. Each hardness traverse shall be located 2 mm below the surface of the weld toe. b. No hardness reading shall exceed HV 248. VI.11 INTERNAL COATING Vessels shall be internally coated with a product suitable for sour service (see COM-SU-2.02). August 2010 (E) © 2005–2010 Chevron U.S.A. Inc. All rights reserved. 48 of 48 ROSEBANK FEED PROJECT ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS DOCUMENT NO: ROS-PGEN-MEC-STD- CHV-0000-00036-01 H01 21-OCT-2013 ISSUED FOR USE JG D01 03-Oct-2013 Issued for Internal Review JG REV DATE DESCRIPTION ORIG APPROVED BY: COMPANY APPROVAL: DATE: DATE: Document No. Project Area Discipline Type Originator Package CHK Sequence No. ROS PGEN MEC STD CHV 0000 00036-01 APPR Revision No. H01 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 Change Log Rev Section Change Description Design Data Uncertainties Section Uncertainty ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 2 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 TABLE OF CONTENTS I. SCOPE.................................................................................................................................................................. 4 II. CHANGES TO THE SPECIFICATION.......................................................................................................................... 4 1.0 SCOPE.................................................................................................................................................................. 4 2.0 REFERENCES......................................................................................................................................................... 5 3.0 GENERAL REQUIREMENTS .................................................................................................................................... 8 4.0 MATERIALS .......................................................................................................................................................... 9 5.0 ENGINEERING .................................................................................................................................................... 10 6.0 FABRICATION ..................................................................................................................................................... 15 7.0 INSPECTION AND TESTING .................................................................................................................................. 17 9.0 IDENTIFICATION AND MARKINGS........................................................................................................................ 19 11.0 DOCUMENTATION REQUIREMENTS .................................................................................................................... 20 APPENDICES .............................................................................................................................................................. 20 APPENDIX III .............................................................................................................................................................. 20 APPENDIX IV .............................................................................................................................................................. 20 APPENDIX V ............................................................................................................................................................... 20 (ADD) APPENDIX VII – STANDARD DRAWINGS ............................................................................................................. 20 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 3 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 I. SCOPE 1. This Location Addendum Specification (LA) defines additional requirements for [CUE]. 2. The requirements in this LA are modifications to the requirements in CES document [PVM-SU-8.00]. 3. The type of modification shall be defined and indicated in subsequent text as follows: (ADD) - Indicates the following statement(s) is/are added to the CES referenced text. (DELETE) Indicates the following statement(s) is/are deleted from the CES referenced text. (REPLACE WITH)- Indicates the following statement(s) is/are revision(s) to the CES referenced text. 4. In case of conflict, requirements in this LA take precedence, but in no case will a less stringent requirement be used unless clearly stated in this LA that the requirement specifically replaces the more stringent requirement. II. CHANGES TO THE SPECIFICATION The following section/paragraph numbers correspond to those in CES document [PVM-SU-8.00]. 1.0 SCOPE 1. (REPLACEWITH)- This specification governs pressure vessels provided in accordance with the EN 13445 Unfired Pressure Vessels or ASME Boiler and Pressure Vessel Code for the Rosebank Project. 2. (REPLACEWITH)- This specification may be supplemented with other requirements such as vessel data sheets (see PMV-DS-8.00 or approved equivalent), Project Technical Requirements, Standard Drawings (see Appendix VII) and/or other supplementary specifications (for vessels in specific services, such as three-phase separators). 3. (REPLACEWITH)- The set of combined documents in Section 1.0 item 2, above, define the minimum acceptable requirements for the design, fabrication, inspection and testing of unfired pressure vessels suitable for installation on a floating production, storage and offloading unit (FPSO). ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 4 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 4. (REPLACEWITH)- Company reserves the right to procure pressure vessels in accordance with this specification even though they may be outside the formal scope of EN 13445 or ASME B&PV Code. 12. (ADD)- This LA applies to Chevron’s CUE offshore operations for the Rosebank Project. 13. (ADD)- Legacy Codes and Standards: A number of Chevron’s current UK assets were built to individual oil company and contractor’s standards and specifications, working to the legislation, codes and standards current at that time. When undertaking modifications and/or tie-ins to systems on these assets, it is necessary to review those standards to ensure compatibility with that which is specified in this Specification. 14. (ADD)- Pressure vessel or pressure equipment listed in PED97/23, Article 1, “Scope and definitions”, Paragraph 3 is not required to comply with PED97/23. However, other requirements specified in this specification shall be met. 1.1 Responsibilities 3. (ADD)- Suppliers scope of supply for each pressure vessel shall include Process Design and Guarantee, as specified in the data sheets. 4. (ADD)- The Supplier shall guarantee the mechanical design and workmanship of each vessel. The Supplier shall also guarantee the mechanical and structural integrity of all associated equipment within the scope of supply. 2.0 REFERENCES 2.1 Purchaser Documents (ADD)- All references in this document to the original Chevron Engineering Standards (for example: PVM-SU-8.01) are to be replaced by the Local Addendum of the same standard (for example ROS-PGEN-MEC-STD-CHV-0000-00037-00). (ADD)- ROS-PGEN-PIP-STD-CHV-0000-00011-00 (PIM-DU-5155) Piping Flexibility and Stress Analysis 2.2 Standard Drawings (ADD) See Appendix VII for copies of the referenced standard drawings (DELETE)- GF-C1 030 Standard Nozzle and Manholes for Thick-Walled Pressure Vessels 2.3 Industry Standards (ADD)- Codes and Standards ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 5 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 The codes and standards referenced below are the latest available at the time of preparation of this revision. When applied on Chevron projects and modifications any new legislation and standards including the latest revisions and updates must be identified, referenced and used. The selection of the appropriate code/standard must ensure that all aspects of the Essential Safety Requirements of legislation are met. PD 5500 (ADD) PD 5500 Annex Z Unfired Fusion Welded Pressure Vessel Code. Guidance on the application of PD 5500 to pressure vessels falling within the scope of the European Pressure Equipment Directive. BS PD 6550 Explanatory supplement re domed ends, branches and tube sheets. Pressure Vessel Details Part 1: Specifications for davits for branch covers of steel vessels. Part 2: Specifications for Saddle Supports for horizontal vessels BS 5276 CEN EN 286 BS 470 (ADD) BS 6399 (ADD) BS EN 10228 CEN EN 13445 (ADD) Part 7 (PD CR) ISO 16528 (ADD) ISO 9000 CEN EN ISO 21457 Simple unfired pressure vessels designed to contain air or nitrogen Specification for Inspection, Access and Entry openings for pressure vessels Loading for Buildings, Part 2: Code of Practice for Wind Loads. Non-Destructive Testing of steel forgings, Parts 1 to 4. Unfired pressure vessels. Part 1: General Part 2: Materials Part 3: Design Part 4: Fabrication Part 5: Inspection and testing Part 6: Requirements for the design and fabrication of pressure vessels and pressure parts constructed from spheroidal graphite cast iron. Part 8: Additional requirements for pressure vessels of aluminum and aluminum alloys Guidance on the use of the conformity procedures. Boilers and pressure vessels Part 1: Performance requirements Part 2: Procedures for fulfilling the requirements of ISO 16528-1 Quality Management System Petroleum, petrochemical and natural gas industries - Materials selection and corrosion control for oil and gas production systems ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 6 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 CEN EN ISO 15156 Petroleum and natural gas industries - Materials for use in H2Scontaining environments in oil and gas production Part 1 : general principles for selection of cracking-resistant materials Part 2 : cracking-resistant carbon and low alloy steels, and the use of cast irons Part 3: cracking-resistant CRAs (corrosion-resistant alloys) and other alloys (ADD)2.4 EU/UK/National Equivalents Where references are made in PVM-SU-8.00 to the requirements of US and Canadian Standards Bodies, the equivalent EU/UK/National standards shall be substituted and applied when appropriate. Where references are made in PVM-SU-8.00 to US approval bodies such as UL and FM, the equivalent EU/UK/National bodies shall be substituted and referred to when appropriate. Where dimensions in PVM-SU-8.00 given in US imperial (English) units, the equivalent SI units shall be substituted. 2.5 Legislation The Legislation, codes and standards referenced below are the latest available at the time of preparation of this revision. When applied on European Chevron projects and modifications any new legislation and standards including the latest revisions and updates must be identified, referenced and used. 2.6 EU Directives The following EU Directives are applicable within the European Union; they are legal requirements. European nations outside the EU, such as Norway, also recognize these Directives: • ATEX : Equipment in Flammable Environments 94/9/EC • PED : Pressure Equipment Directive 97/23/EC • EMC : Electromagnetic compatibility 89/336/EC • CE Marking Directive (93/68/EEC) • Dangerous Substances Directive (67/548/EEC) ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 7 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 • Machinery Equipment Directive 2006/42/EC • The Control of Noise at Work Regulations 2003/1 0/EC: 2005. 2.7 National Regulations European Nations have their own nationally specific legislation that is applicable within their national borders. Projects must ensure that national legislation is identified and complied with on all CUE projects. Specific UK legislation applicable to this Local Addendum is listed below as an example. UK Regulations: 3.0 • Health and Safety at Work, etc., Act 1974 • The Provision and Use of Work Equipment Regulations (PUWER) 1998 • The Pressure Equipment Regulation 1999 (SI 1999/2001) • The Pressure Systems Safety Regulations 2000 • The Simple Pressure Vessels (Safety) Regulation 1991 (SI 1991/2749) & 1994 (SI 1994/3098) • The Control of Noise at Work Regulations SI 2005/1643 • The Equipment and Protective Systems in Potentially Explosive Atmospheres Regulations (EPSR) SI1996:192, SI1998: 81 and SI2001: 3766. • The Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) SI2002: 2776 • The Offshore Installations Prevention of Fire and Explosion and Emergency Response Regulations (PFEER) SI1995:743 • The Chemicals (Hazard Information and Packaging for Supply) Regulations (SI 716:2009) GENERAL REQUIREMENTS 1. (REPLACEWITH)- Pressure vessel design, fabrication, testing and inspection shall be in accordance with this specification. All Addenda issued through the date of the Agreement, Contract, or Purchase Order shall apply in full. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 8 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 (1) Pressure vessel design, fabrication, inspection and testing shall conform to EN 13445 (Unfired Pressure Vessels), other relevant harmonized EN standard and Project preferred standards. EU standards take precedence over US standards such as ASME B&PV Code in case of conflict. If pressure vessel/exchanger is built to ASME B&PV Code, the requirements below shall be met. • If pressure vessel is fully built to ASME B&PV Code, the demonstration of compliance with the ESR’s of PED is required. CE marking and the full responsibility of Supplier are compulsory. • If partial pressure components are built to ASME B&PV Code, the relevant requirements stated in EN 13445 shall be confirmed. (2) The requirements addressed in this specification and other Project CES standards with their addenda shall be confirmed wherever they are not addressed in EN standards or they are more stringent. (3) In case of conflict between EN standard and Rosebank Project specification/standard, Supplier shall bring it to Company’s attention immediately for a resolution. (4) Note that requirements addressed in this specifications might refer to ASME Code. But the above requirements shall be applied for regulatory compliance and CE marking. 3. (REPLACEWITH)- Unless specified otherwise by Company, pressure vessels shall have a minimum service life of 25 years, and internals that are readily replaceable shall have a minimum service life of 10 years. 5. (REPLACEWITH)- All flanges shall be in accordance with the latest edition of ASME B16.5, or ASME B16.47 with demonstration of compliance with ESR’s of PED is required. 6. (REPLACEWITH)- Piping outside vessels, if included, shall conform to ASME B31.3. The demonstration of compliance with ESR’s of PED is required. 4.0 MATERIALS 1. (REPLACEWITH)- Materials and construction for pressure vessels shall conform to European harmonized standard. Any material other than those specified in European standard shall be covered by a “European Approval for Materials” (EAM) conforms to applicable Essential Safety Requirements for material. Supplier shall note that ASME materials are not directly usable. Supplementary requirements must be specified to permit compliance with essential requirements. Particular Material Appraisal (PMA) is the process by which the supplier can ensure the proposed ASME material that is not in a harmonized standard or covered by EAM conforms to the applicable Essential Safety Requirements (ESR’s). Note this specification ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 9 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 may refer to ASME material. But the above specified procedure shall be applied for those ASME materials for regulatory compliance and CE marking. All pressure containing material manufacturers must be EU Certified. 5.0 ENGINEERING 5.1 General Engineering 1. (REPLACEWITH)- Supplier shall be responsible for the detailed mechanical design of pressure vessels. The selection of the appropriate code must ensure that all aspects of the Essential Safety Requirements (ESR’s) of the above legislation are met. The following are general guidance: • Vessels designed to CEN EN 13445 are deemed to comply fully with PED. • Vessels designed to PD 5500 require application of Annex Z to comply with the ESR’s of the PED. • Vessels designed to ASME VIII will require demonstration of compliance with the ESR’s of PED. • The Pressure Vessel designer, fabricator and supplier shall be experienced in the provision of pressure vessels of similar diameter, thickness and length/ height. They shall operate under the supervision of a Notified Body as required by the legislation • The design of the pressure vessel size, dimensions and weight shall consider the installation and space requirements offshore as well as transportation and handling needs. • Where references are made in to the requirements of US and Canadian Standards Bodies such as NEC, NEMA, NFPA, IEEE etc., the equivalent EU/UK standards shall be substituted and applied when appropriate. 11. (DELETE)5.2 Design Requirements 1. (ADD)• corrosion environment • internal design temperature • external blast (explosion) over pressure ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 10 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 • cyclic loading • snow / ice loading • vibration • lifting and transportation 3. (REPLACEWITH)- The Maximum Permissible Pressure per EN 13445 or MAWP per ASME B&PV Code shall be based on the actual metal thickness less corrosion allowance. 6. (REPLACEWITH)- The Minimum Allowable Temperature TSmin per EN 13445 or MDMT per ASME B&PV Code shall be as shown in vessel datasheet, which shall apply to both pressure containing and vessel support components. They shall not be warmer than 10°C. 11. (ADD)- The vessel will be installed and operated on an FPSO unit and the Supplier shall ensure materials, design and construction are suitable for the extreme marine environment that the equipment will be subjected to in service. 12. (ADD)- The vessel will subject to heavy sea motions (roll, pitch, yaw, heave, surge & sway) of the FPSO. The motion datasheet identifies the motion and acceleration values the equipment will experience. Please refer to the motion datasheet with the requisition & Project specification, ROS-PGEN-ADM-SPC-WLP-0000-00001-00, “Site conditions, Environmental Loads & Available Utilities” for FPSO motion specific design requirements. 13. (ADD)- Supplier shall consider the magnitude and effect of static and dynamic loads on the vessel including externals/internals and their supports in the design due to the motion and acceleration loads, dynamic effects on contained liquids, inertia and fatigue loads on equipment, supports and structures. 14. (ADD)- In addition to the effects of the ships motions over the design life, fatigue analysis for pressure component such as shell, heads, nozzles, flanges and pressured bolting joints/welding joints shall conform to EN 13445 Part 3 Section 17 and Section 18 or PD 5500 Annex C with the exception that the fluctuations can be ignored if stress range (difference of maximum and minimum) does not exceed 5% of maximum permissible pressure regardless of number of load cycles. Note: Local stress fluctuations occur in shell or head such as shell to saddle joint, head to skirt joint, internal support to shell joint… etc. shall be evaluated per Section 18 of EN 13445 Part 3 if the stress range exceeds 5% of maximum permissible pressure. All pressure components shall be guaranteed. 15. (ADD)- For all vessel supports and process internals the Supplier shall carry out fatigue assessment due to stress amplitudes, including liquid surge effects using the dynamic ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 11 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 accelerations and hull deflections, imposed by the ships motions, and fatigue due to nozzle loadings. All supporting structural shall be guaranteed. 16. (ADD)- The local stress at shells, heads and nozzles due to external loads on nozzles and clips, thermal expansion loads and support reactions should be evaluated in accordance with EN 13445 Part 3 Section 16 or WRC-107/297, WRC-537 whichever is more stringent. Extrapolation of geometric parameter curves in WRC 107/297 or WRC-537 shall not be permitted. 17. (ADD)- Vessels shall be designed for a blast load as specified on the vessel datasheet. The loads shall be applicable in both vertical and lateral directions with the worst condition governing. Blast loads shall be applied concurrently with normal operating loads. The blast load and wind lad should not be considered simultaneously. 18. (ADD)- The pressure vessel shall be of proven design with a track record on FPSO unit. 5.5 Nozzles, Manways, Bosses and Other Openings 1. (REPLACEWITH)- Unless specified otherwise by Company, all vessel nozzles shall be flanged, with a minimum size of 2" NPS (DN 50). 2. (REPLACEWITH)- Flanged nozzles smaller than 2" NPS (DN 50) shall not be allowed unless specifically approved in writing by Company, and shall never be smaller than 3/4" NPS (DN 20). 5. (REPLACEWITH)- “Set-on" nozzle designs are not acceptable. “Set-in” design shall be double welded from both inside and outside. 7. (REPLACEWITH)- Nozzles shall be either long weld neck flanges, or seamless pipe. • Long weld neck flanges are preferred by Company for all nozzles 3" (DN 80) and smaller. • Flanges used in built-up construction shall be forged steel weld neck type, bored to match the inside diameter of the pipe nozzle neck. • Socket welded or slip-on flanges shall not be acceptable, except on manways. • Studded pad-type nozzles shall not be permitted. 10. (REPLACEWITH)- Vessel nozzle neck thickness shall be in accordance with the EN 13445 Part 3, but with the following minimum thickness requirements. Minimum schedules shown refer to nozzle thickness in the new condition. When overlay construction is used, combined ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 12 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 thickness of the overlay and base metal may be used to qualify for the minimum thickness requirement as shown in the table. Nominal Diameter (DN) Nom. Pipe Size Min. Schedule 50 to 80 2” to 3” 160 100 4” 120 150 to 250 6” to 10” 80 300 to 400 12” to 16” 60 450 to 500 18” to 20” 30 600 24” 40 12. (REPLACEWITH)-Wherever possible, nozzle reinforcing pads should not be used since the reinforcing pads prevent external UT of the nozzle welds. Integrally reinforced or selfreinforced nozzles are recommended. However, if removal of reinforcing pads results increasing the thickness of the vessel shell to get the strength, Supplier shall submit the written notice for Purchaser review and approval. • Nozzle design details and reinforcement shall conform to Standard Drawing GFC14311. • As an alternative to the Standard Drawing, nozzle reinforcement calculation per current Code is acceptable, provided the design conforms to all the other requirements listed in this specification. 14. d. (REPLACEWITH)- Reinforcing plates of saddles and nozzles attached to the outside of a vessel shall be provided with at least one telltale hole [maximum size NPS1/4 (DN 8) tap] that may be tapped for a preliminary compressed air and soapsuds test for tightness of welds that seal off the inside the vessel. These telltale holes may be left open or may be plugged when the vessel is in service. If the holes are plugged, the plugging material used shall not be capable of sustaining pressure between the reinforcing plate and the vessel wall. 21. a. (REPLACEWITH)- Unless otherwise specified, process nozzles in the corroded condition shall be checked for their capability of withstanding the forces and moments as shown in ROS-PGEN-PIP-STD-CHV-0000-00011-00 (PIM-DU-5155) “Piping Flexibility and Stress Analysis.” ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 13 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 21. c. (REPLACEWITH)- Local stress at the nozzle connection shall be calculated per Paragraph 5.2.16 in this specification. 5.6 Internals 1. (REPLACEWITH)- Internal non-pressure-containing parts, such as trays and catalyst support beams, internal equipment, such as cyclones and grids, and attachments welds to vessel, shall be designed using allowable stress of material as same as the pressure containing parts. 14. a. (REPLACEWITH)- Due to the motions of the FPSO, Supplier shall design all vessels to maintain performance comparable to similar vessels installed on a fixed foundation. This will require Supplier to pay close attention to the design of vessel internals and may require the installation of additional baffle plates or other motion suppression internals to maintain acceptable performance during dynamic motion and sloshing effects of fluids within the vessel. 16. (ADD)- All internals of bolted construction shall be removable through manways unless otherwise specified in datasheets or approved by Company. 17. (ADD)- All portions of the vessel, including internals shall be completely self- draining. 18. (ADD)- The Supplier shall ensure that there is sufficient access into the vessel for installation of internals and access for operation and maintenance requirements for internals. 19. (ADD)- All internal bolting shall be positively locked by a lock nut and wire. 5.7 External Attachments 5. i. (ADD)- The Supplier shall provide an assessment and Supplier checklist for LOLER 1998 regulations (Lifting Operations and Lifting Equipment Regulations). This applies to lifting operation and lifting gear being provided as part of the purchase order scope, ie. Lifting beam, slings and shackles. 7. c. (ADD)- Insulation supports, stiffening rings and external attachments shall be designed and constructed to prevent the channeling and hold up of rain water or sea spray. Drain holes or gaps to prevent the accumulation of water shall be provided to enhance natural draining. 9. (ADD)- All materials welded directly to the pressure retaining envelope shall be same materials or the same P number and group number. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 14 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 5.8 Vessel Supports 5.8.1 General 1. a. (REPLACEWITH)- Support bolting design (size, number, minimum spacing, etc.) shall be based on use of ASTM SA-325 bolting with PMA or equivalent European Standard. 3. (REPLACEWITH)- Wind, motion and transportation loads per datasheets and Project Specification, “Site Condition, Environmental Loads & Available Utilities” shall be taken account in support design. Unless otherwise stated, Exposure Category D (wind from open body of water) shall be assumed and importance factor for wind load shall be 1.15. Unless otherwise specified by Company, transportation design loads shall be based on a lateral acceleration of 0.65g acting along both the longitudinal axis and the transverse axis, and a vertical acceleration of 1.5g as a minimum. The allowable stress may be increased by 33% for the transportation design condition. 5.8.2 Horizontal Vessels 5. (REPLACEWITH)- Horizontal vessel shells shall be analyzed in accordance with EN 13445 Part 3, Paragraph 16.8. If the analysis is accordance with L. P. Zick's "Stresses in Large Horizontal Cylindrical Pressure Vessels on Two Saddle Supports", the requirements of local stress, instability per EN 13445 Part 3 Section 16 should be confirmed. 5.8.3 Vertical Vessels 1. c. (REPLACEWITH)- Stress analysis for skid shall conform to EN 13445 Part 3 Paragraph 16.12. If skid is built to ASME B&PV Code, the allowable stress value for skirt thickness shall be calculated using a weld joint efficiency of 0.55 and related requirements addressed in EN 13445 Part 3 Paragraph 16.12 shall be confirmed. 2. (DELETE)3. a. (3) (ADD)- The skirt ring shall have a nominal height of 10” (250mm) above top of steel grade unless shown otherwise on the vessel mechanical data sheet. 6.0 FABRICATION 6.1 General (ADD)-Note: The following requirements addressed in this section (6.0 FABRICATIOM) refer to ASME B&PV Code. But the requirements specified in Section 3.0 “GENERAL REQUIREMENTS”, Paragraph 1 shall be applied for regulatory compliance and CE marking. In addition to the note, the requirements in PED97/23 ANNEX I, Section 3.1.1 for preparation ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 15 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 of the component parts, Section 3.1.2 for permanent joining and Section 3.1.5 for traceability shall be confirmed. 21. (ADD)- If pressure vessels are built EN 13445, EN ISO 15614, “Specification and qualification of welding procedures for metallic materials”, EN 287, “Qualification test of welders” and EN 473, “Non-destructive testing - Qualification and certification of NDT personnel” shall be referred. The requirements addressed in EN 13445 Part 3, 4 and 5 shall be met. In case of conflict, the more stringent requirement shall take precedence. 22. (ADD)- Gouges shall be welded with an approved procedure and ground flush and smooth. 6.2 Qualification of Welding Procedures and Welders 6.2.1 Welder and welding Operator Qualification (REPLACEWITH)- Prior to the start of fabrication, welding personnel as required for pressure equipment and assemblies in PED Categories II, III and IV must be approved by recognized Third Party/Notified Body. Welder qualifications for using the specific qualified welding procedure specification (WPS) and certificates with picture identification shall also be submitted to Company for review and acceptance. 6.3 Welding Processes (ADD)- For pressure equipment in categories II, III and IV, operating procedures and personnel must be approved by a competent third party which, at the manufacturer's discretion, may be: • a notified body • a third-party organization recognized by a Member State as provided 6.3.3 Submerged-Arc Welding (SAW) 5. (REPLACEWITH)- SAW is not permitted for austenitic stainless steel unless approved by Company. 6.5 Heat Treatment and Stress Relieving 1. (REPLACEWITH)- Post weld heat treatment (stress-relief) shall be provided in accordance with ASME Code, and as specified in the Technical Requirements or vessel data sheet. Vessels subject to sulfide stress cracking (see Appendix VI) shall be postweld heat treated. The requirements addressed in EN 13445 Part 4 Section 9 “Forming of Pressure Parts” and Section 10 “Post Weld Heat Treatment (PWHT)” shall be met and shall take precedence if they conflict with ASME B&PV Code. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 16 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 4. (REPLACEWITH)- Welding shall not be allowed on pressure vessels after stress relieving, unless specifically authorized in writing by Company and in accordance with EN 13445 Part 4, Paragraph 10.2.3. 7.0 INSPECTION AND TESTING 7.1 General (ADD)-Note: The definitions and requirements addressed in this section (7.0 INSPECTION AND TESTING) refer to ASME B&PV Code. But the requirements specified in Section 3.0 “GENERAL REQUIREMENTS”, Paragraph 1 shall be applied for regulatory compliance and CE marking. In addition to the note, the requirements in EN 13445 Part 5 (Inspection and Testing) shall be confirmed. In case of conflict between EN standard and this specification, Supplier shall bring it to Company’s attention immediately for a resolution. 3. (REPLACEWITH)- Company inspection shall not relieve Supplier of responsibility for all examinations necessary to assure compliance with European harmonized standards and the requirements of this specification and the vessel data sheet. 6. (ADD)- Approval of non-destructive testing personnel as required for pressure equipment and assemblies in PED Categories II, III, and IV must be approved by recognized Third Party / Notified Body. PED Group and Categories shall be indicated against each equipment. 7. (ADD)- Unless otherwise is specified by the Purchaser in writing, the following shall apply: • A Notified Body shall be engaged by the Supplier to certify that the Essential Safety Requirements of the Design, fabrication and construction requirements of the Pressure Equipment Regulations have been met. • The Purchaser, at its own discretion, will appoint an employee or an authorized agent to monitor material quality, workmanship and conformance to data supplied, standards and codes during manufacture, fabrication, testing etc. The said inspector is empowered to accept or reject, at any stage, any item which he considers fails to satisfy the requirements. • The Purchaser shall appoint an Independent Competent Person (ICP) (an independent organization) who is authorized to survey and inspect all aspects of design, materials, fabrication, installation and commissioning of equipment, plant and facilities, and to issue a Certificate of Fitness certifying that these comply with all requirements. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 17 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 7.2 Non Destructive Examination 4. (ADD)- EN 13445 Part 5 (Inspection and Testing), Section 6.6, “Non-destructive testing of welded joints” is applicable to NDE of pressure vessel. The Extent of NDE listed in Table 6.6.1-1, 6.6.2-1 and NDE method, acceptance criteria listed in Table 6.6.3-1 shall be carried out. These requirements shall take precedence over those referring to ASME B&PV Code in case of conflict. 7.3 Radiographic Inspection 1. (REPLACEWITH)- Addition to the requirements in Paragraph 7.2.4 above, all butt welds (including butt welds for flange-to-pipe nozzles and nozzles constructed of rolled plate) shall be spot radiographed. • One radiograph shall be taken showing not less than 14" (350 mm) of weld for each longitudinal and each circumferential joint in the shell and heads. • One spot radiograph (14") (350 mm) shall be taken of each butt weld in the skirt of a vertical vessel. 5. b. (REPLACEWITH)- Should additional repairs be required, and then Supplier shall repair all defects in accordance with EN 13445 Part 4, Section11. Weld repaired areas shall be nondestructively examined per EN 13445 Part 5. Supplier shall bear all costs for the additional radiographs and repairs. 5. d. (DELETE)7. (REPLACEWITH)- Radiographic film shall be retained by Supplier for five year after the date that the Authorized Inspector approves the Manufacturer's Data Report. 7.4 Hydrostatic Pressure Testing 1. (REPLACEWITH)- After completion of all fabrication, welding, visual inspection, NDE, radiography, stress relieving and telltale-hole air tests, Supplier shall perform a hydrostatic test in accordance with PED 97/23 ANNEX I, Paragraph 3.2.2 (Proof test) and Paragraph 7.4 (Hydrostatic test pressure). • Hydrostatic tests shall be performed in the presence of, and with the approval of, Contractor's Authorized Inspector and/or Company. • Vessels shall not have been previously hydrotested by Supplier without Company authorization. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 18 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 • Hydrostatic testing of piping outside the limits of this specification shall be as prescribed in project specification ROS-PGEN-PIP-STD-CHV-0000-00002-00, “General Piping Fabrication, Inspection and Testing with Addendum”. 8. a. (REPLACEWITH)- For pressure vessels, the hydrostatic test pressure must be no less than that corresponding to the maximum loading to which the pressure equipment may be subject to service taking into account its maximum allowable pressure and its maximum allowable temperature, multiplied by the coefficient 1.25, or the maximum allowable pressure multiplied by the coefficient 1.43 whichever is the greater. 8. b. (DELETE)14. (ADD)- The Supplier shall ensure that the vessel is designed with adequate means of venting during the hydrostatic fill. 9.0 IDENTIFICATION AND MARKINGS 1. (REPLACEWITH)- Pressure vessels shall be certificated. PED conformity category and fluid Groups should be stated on vessel datasheets. The Supplier shall re-confirm PED groups and categories. 2. (REPLACEWITH)- Nameplate of pressure vessel shall be provided. Nameplates shall be located so that they are easily accessible after installation and lettering shall be a minimum of 4 mm (3/16”) high. The required information per PED 97/23 Annex I, 3.3 shall be shown on the nameplate. ASME B&PV Code nameplate and Code stamp are not required. Addition to required information per PED, the following data shall be engraved: • Corrosion Allowance • Shell Material and Thickness • Head Material, Thickness and Type • Vessel Name (Service) and Tag Number • Purchase Order Number • Vessel Weights - Dry, Operating and Hydrostatic Test 3. (REPLACEWITH)- CE marking and Declaration of Conformity shall be provided. The DoC form should conform to PED 97/23 Annex VII. ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 19 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 11.0 DOCUMENTATION REQUIREMENTS 1. (REPLACEWITH)- Supplier shall provide documentation in accordance with design code and the vessel data sheet or Technical Requirements. 2. a. (REPLACEWITH)- Design code calculations. 2. c. (REPLACEWITH)- Weld Map with WPS Identification. 7. a. (REPLACEWITH)-EC type Examination Certificates and Declaration of Conformity (DoC) 7. c. (REPLACEWITH)-Calculations. APPENDICES (ADD)-Note: The terms and requirements addressed in these appendixes (Appendix I thru. Appendix VI) might refer to ASME B&PV Code. But the requirements specified in Section 3.0 “GENERAL REQUIREMENTS” Paragraph 1 and Section 4.0 “MATERIALS” Paragraph 1 shall be applied for regulatory compliance and CE marking. In addition to the note, the requirements in EN 13445 Part 5 (Inspection and Testing) shall be confirmed. In case of conflict between EN standard and this specification, Supplier shall bring it to Company’s attention immediately for a resolution. APPENDIX III III.2 Design (ADD)-Corrosion allowable for stainless steel shall be a minimum 0f 0.8 mm (1/32”). III.4 Hydrostatic Pressure Testing (REPLACEWITH)- Test fluid for solid austenitic stainless steel or cladded vessels shall not contain more than 50 ppm chloride content. APPENDIX IV IV.6 Hydrostatic Test 3. (REPLACEWITH)- The chloride content of hydrotest water shall not exceed 50 ppm. APPENDIX V (DELETE)-Delete the entire appendix. (ADD) APPENDIX VII – STANDARD DRAWINGS (ADD) The following standard are also provided electronically at the end of appendix VII: ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 20 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 21 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 22 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 23 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 24 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 25 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 26 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 27 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 28 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 29 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 30 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 31 of 32 Rosebank FEED Project ADDENDUM TO PVM-SU-8.00 GENERAL SPECIFICATION FOR PRESSURE VESSELS ROS-PGEN-MEC-STD-CHV-0000-00036-01 Rev H01 ROS-PGEN-MEC-STD-CHV-0000-00036-01 Page 32 of 32
