This pressure vessel specification discusses general pressure vessel requirements including engineering design, fabrication, inspection, testing, painting, identification and marking, preparation for shipping and storage in compliance with the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1.

This specification will define the minimum acceptable requirements of unfired pressure vessels suitable for installation in energy industry.

1. Introduction

This specification governs pressure vessels provided in accordance with the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1; pressure vessels, 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 6500F (3430C) or less.

This specification may be supplemented with other requirements such as vessel data sheets, Project Technical Requirements, Standard Drawings and/or other supplementary specifications (for vessels in specific services, such as three-phase separators).

The combined documents mentioned in this specification define the minimum acceptable requirements for the design, fabrication, inspection and testing of unfired pressure vessels suitable for installation in energy industry.

Buyer 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 should conform to all ASME Code requirements, except for application of the ASME Code Stamp and National Board Registration.

The most recent issue of the standards, specifications and codes (using the latest addenda issued through the date of this agreement) should be considered as a part of this Specification.

In addition to project technical requirements, pressure vessels should meet all requirements of the governmental authorities having jurisdiction at the location where the pressure vessels is to be installed, as stated in the Agreement, Contract, or Purchase Order, as applicable.

Vessels should be designed to meet the operating and design conditions listed on Vessel Data Sheets. Shell diameter, length and nozzle sizes shown are considered as minimum unless defined otherwise.

Vessels should be equipped with all attachments such as nozzles, manways, tray support rings, and insulation clips.

1.1 Responsibilities

Supplier should 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.

Written permission must be obtained before any work is subcontracted.

1.2 Conflicts and Exceptions

All conflicts between this specification or other technical requirements and the applicable codes and standards should be submitted in writing for approval.

2. References

The following documents are considered part of this specification. Use the edition of each referenced document in effect on the date of the publication of this specification.

Industry Standards

American Institute of Steel Construction (AISC) . Manual of Steel Construction

American Society of Civil Engineers (ASCE) 7. Building Code Requirements for Minimum Design Loads in Buildings and Other Structures

American Society of Mechanical Engineers (ASME)

Boiler and Pressure Vessel Code Section II - MaterialsNote: SFA requirements for welding consumables may be located in Part C of Section IISection VIII - Rules for Construction of Pressure Vessels, Division 1Section VIII - Rules for Construction of Pressure Vessels, Division 2, Alternative RulesSection 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

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,Last Modified 2015.

3. General Requirements

The design, materials, fabrication, inspection, testing and documentation of pressure vessels should 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 should apply in full.

Unless specified otherwise, Supplier should be solely responsible for detailed process design.

  • Any vessel sizing or design criteria provided, including diameter, length, nozzle sizing, internal configurations, etc., should be considered preliminary and confirmed by Supplier.
  • Reduction of specified sizing or design criteria should not be acceptable without prior approval, in writing.

Unless specified otherwise, pressure vessels should have a minimum service life of 20 years, and internals that are readily replaceable should have a minimum service life of 10 years.

Pressure vessels specified for “sour service” should be in accordance with NACE MR-01-75.

All flanges should be in accordance with the latest edition of ASME B16.5, or ASME B16.47.

Piping outside the limits of the ASME Code, if included, should conform to ASME B31.3.

4.0 Materials

Materials and construction for pressure vessels should conform to the ASME Code and with the requirements of this Specification, including the applicable Appendices, unless otherwise indicated on the Buyer-approved vessel drawings.

Any recommended material substitutions that do not meet the above requirements should be submitted to the Buyer for review and approval. For example, Supplier may, with Buyer approval, upgrade material in lieu of impact testing.

Castings should be prohibited, unless agreed to by the Buyer in writing.

All materials should be new and free from mill scale.

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.

For additional information on unfired pressure vessels, please see engineering design including fabrication and Inspection, Testing, Painting, Marking, Preparation for Shipping and Storage.