1 Scope
This standard specifies the basic requirements for the welding of steel, aluminium, titanium, copper, nickel and composite metal pressure vessels.
This standard is applicable to the pressure vessels welded by gas welding, shielded metal arc welding, submerged-arc welding, gas tungstun arc welding, gas metal arc welding, plasma arc welding, electro-gas welding and stud welding.
This standard is not applicable to gas cylinder.
2 Normative References
The following documents are indispensable for the application of this document. For dated references, only the dated edition applies. For undated references, the latest edition (including all the amendments) of the normative document applies.
GB/T 985.3 Recommended Joint Preparation for Gas-Shield Arc Welding on Aluminium and Its Alloys
GB/T 3670 Coated Electrodes for Copper and Copper Alloys
GB/T 9460 Copper and Copper Alloy Wires and Rods
NB/T 47002 (all parts) Explosion Welded Clad Plate for Pressure Vessels
NB/T 47014 Welding Procedure Qualification for Pressure Equipment
NB/T 47018 (all parts) Technical Permission of Welding Materials for Pressure Equipment
JB/T 4745 Titanium Welded Vessels
TSG 26002-2010 Regulations of Assessment on Special Equipment Welding Operation Personnel
3 General Welding Specification
3.1 General requirements
3.1.1 The welding of pressure vessels shall not only comply with the requirements of this standard, but also shall meet the technical requirements of design document.
3.1.2 In addition to the requirements of this standard, the achievements that are proven to be effective through experimental study and practices may be used for the welding of pressure vessels after being approved by the relevant parties and listed in the enterprise standards.
3.2 Welding materials
3.2.1 Welding materials include welding electrode, welding wire, solder strip, flux, gas, electrode and gasket, etc.
3.2.2 Selection principles for welding materials:
a) The mechanical properties of weld metal shall be higher than or equal to the specified limit of base metal; where it is necessary, other properties shall not be lower than the corresponding requirements of base metal; or the mechanical properties and other properties shall meet the technical requirements specified in the design document;
b) Suitable welding materials shall match the reasonable welding process to ensure that the properties of welded joint can still meet the requirements of design document and service after undergoing manufacturing process;
c) The manufacturing (installation) organization shall know the welding property of welding materials; the welding materials used for pressure vessels shall have welding test or practice basis.
3.2.3 The welding materials used for pressure vessels shall be in accordance with those specified in NB/T 47018.
3.2.4 Welding materials shall be provided with product quality certification and shall meet the requirements of relevant standards. The using organization shall carry out acceptance or reinspection according to the requirements of quality management system and relevant standards, and the welding materials may be used after passing the acceptance or reinspection.
3.3 Weld positions are classified into flat weld, vertical weld, horizontal weld and overhead weld. See Appendix A for the specified method and scope for weld position.
3.4 Welding process qualification and welders
3.4.1 The welding process for welding the following welds shall be qualified through assessment according to NB/T 47014:
a) Weld of pressure parts;
b) Weld welded with pressure parts;
c) Tack weld of the above-mentioned ones.
d) Surface overlaying and repair welding of the base metal of pressure parts.
3.4.2 The welder welding the following welds shall be pass the examination according to TSG 26002:
a) Weld of pressure parts;
b) Weld welded with pressure parts;
c) Tack weld permanently fused into the above-mentioned permanent welds;
d) Surface overlaying and repair welding of the base metal of pressure parts.
Foreword I
1 Scope
2 Normative References
3 General Welding Specification
4 Welding Specification for Steel Pressure Vessels
5 Welding Specification for Aluminium Pressure Vessels
6 Welding Specification for Titanium Pressure Vessels
7 Welding Specification for Copper Pressure Vessels
8 Welding Specification for Nickel Pressure Vessels
9 Welding Specification for Composite Metal Pressure Vessels
Appendix A (Informative) Specified Method and Scope for Weld Position
Appendix B (Informative) Type and Dimension of Special Material Welding Groove
Appendix C (Informative) Recommended Table for Welding Process Specification
Explanation on Compilation
