Detail of GB/T 20801.2-2020

Introduction of GB/T 20801.2-2020

Pressure piping code - Industrial piping - Part 2: Materials 1 Scope This part of GB/T 20801 specifies the basic requirements of materials for pressure piping components, including requirements for the selection of materials, the service restrictions based on material properties, marking, inspection certificate, etc. This part is applicable to the selection and use of materials for pressure piping components defined by GB/T 20801.1. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 229 Metallic materials - Charpy pendulum impact test method GB/T 1220 Stainless steel bars GB/T 1348 Spheroidal graphite iron castings GB/T 2882 Nickel and nickel alloy tube GB/T 3077 Alloy structure steels GB/T 3087 Seamless steel tubes for low and medium pressure boiler GB/T 3091 Welded steel pipes for low pressure liquid transmission GB/T 3098.1 Mechanical properties of fasteners - bolts, screws and studs GB/T 3098.6 Mechanical properties of fasteners - Stainless steel bolts, screws and studs GB/T 3624 Titanium and titanium alloy seamless tubes GB/T 4334 Corrosion of metals and alloys - Test methods for intergranular corrosion of stainless steels GB/T 4437.1 Aluminium and aluminium alloy extruded tubes - Part 1: Seamless tubes GB/T 5310 Seamless steel tubes and pipes for high pressure boiler GB/T 6479 Seamless steel tubes for high-pressure for chemical fertilizer equipment GB/T 6614 Titanium and titanium alloy castings GB/T 6893 Aluminium and aluminium alloys cold drawn(rolled) seamless tubes GB/T 8163 Seamless steel pipes for liquid service GB/T 9439 Grey iron castings GB/T 9440 Malleable iron castings GB/T 9711 Petroleum and natural gas industries - Steel pipe for pipeline transportation systems GB/T 9948 Seamless steel tubes for petroleum cracking GB/T 12228 General purpose industrial valves - Specification of carbon steel forgings GB/T 12229 General purpose industrial valves - Specification of carbon steel castings GB/T 12230 General purpose industrial valves - Specification of stainless steel castings GB/T 12771 Welded stainless steel pipes for fluid transport GB/T 12778 Determination of Charpy impact fracture surface for metallic materials GB/T 13295 Ductile iron pipes, fittings and accessories for water or gas applications GB/T 13401 Steel buttwelding pipe fittings - Technical specification GB/T 14976 Seamless stainless steel pipes for fluid transport GB/T 16253 Steel castings for pressure purposes GB/T 18984 Seamless steel tubes for low-temperature-service piping GB/T 20801.1-2020 Pressure piping code - Industrial piping - Part 1: General GB/T 20801.3-2020 Pressure piping code - Industrial piping - Part 3: Design and calculation GB/T 20801.4-2020 Pressure piping code - Industrial piping - Part 4: Fabrication and assembly GB/T 20801.5-2020 Pressure piping code - Industrial piping - Part 5: Inspection and testing GB/T 20801.6-2020 Pressure piping code - Industrial piping - Part 6: Safeguarding GB/T 21832 (all parts) Welded austenitic-ferritic (duplex) stainless steel tubes and pipes GB/T 21833 Seamless austenitic-ferritic (duplex) stainless steel tubes and pipes GB/T 25137 Titanium and titanium alloy forgings GB/T 26027 Aluminium and aluminium alloys drawn seamless tubes for large circumscribed circle diameter of cross section GB/T 26030 Nickel and nickel alloy forgings GB/T 26057 Titanium and titanium alloy welded tube GB/T 26058 Extruded tube of titanium and titanium alloys GB/T 27684 Seamless and welded fittings for titanium and titanium alloy GB/T 29168.1 Petroleum and natural gas industries - Induction bends, fittings and flanges for pipeline transportation systems - Part 1: Induction bends GB/T 29168.2 Petroleum and natural gas industries - Induction bends, fittings and flanges for pipeline transportation systems - Part 2: Fittings GB/T 29168.3 Petroleum and natural gas industries - Induction bends, fittings and flanges for pipeline transportation systems - Part 3: Flanges GB/T 30059 Seamless corrosion-resisting alloy tubes for heat-exchanger GB/T 31032 Welding and acceptance standard for steel pipings and pipelines GB/T 32964 Welded stainless steel pipes for liquefied natural gas HG/T 20537.3 Technical requirements of welded austenitic stainless steel pipes for chemical plants HG/T 20537.4 Technical requirements of large-diameter welded austenitic stainless steel pipe for chemical plants HG/T 20634 Bolting for use with steel pipe flanges (Class designated) JB/T 5263 Specification for steel casting for power station valves JB/T 7248 Technical specification for low temperature service steel casting for valves NB/T 47008 Carbon and alloy steel forgings for pressure equipment NB/T 47009 Alloy steel forgings for low temperature pressure equipment NB/T 47010 Stainless and heat-resisting steel forgings for pressure equipments NB/T 47013.2-2015 Nondestructive testing of pressure equipment - Part 2: Radiographic testing NB/T 47013.3-2015 Nondestructive testing of pressure equipment - Part 3: Ultrasonic testing NB/T 47014 Welding procedure qualification for pressure equipment NB/T 47028 Nickel and nickel alloy forgings for pressure vessels NB/T 47029 Aluminium and aluminium alloy forgings for pressure vessels SY/T 5037 Submerged arc-welded steel pipe for common fluid service pipeline YB/T 4173 Forged and bored seamless steel pipes with heavy wall for high-temperature service ASTM A333 Specification for seamless and welded steel pipe for low - Temperature service ASTM A671 Specification for electric-fusion-welded steel pipe for atmospheric and lower temperatures ASTM A691 Specification for carbon and alloy steel pipe, electric fusion welded for high pressure service at high temperatures ASTM B361 Standard specification for factory made wrought aluminum and aluminum alloy welding fittings ASTM B366 Standard specification for factory made wrought nickel and nickel alloy fittings ASTM B444 Standard specification for nickel-chromium-molybdenum-columbium alloys (UNS N06625 and UNS N06852) and nickel-chromium-molybdenum-silicon alloy (UNS N06219) pipe and tube ASTM B619 Standard specification for welded nickel and nickel cobalt alloy pipe ASTM B622 Standard specification for seamless nickel and nickel cobalt alloy pipe and tube 3 Terms and definitions For the purposes of this document, the terms and definitions defined in GB/T 20801.1-2020, GB/T 20801.3-2020, GB/T 20801.4-2020, GB/T 20801.5-2020 and GB/T 20801.6-2020 as well as the following apply. 3.1 low temperature and low stress service working conditions that need to meet the following conditions at the same time: a) The maximum working pressure at low temperature is not more than 30% of the maximum allowable working pressure at normal temperatures; b) The sum of axial tensile stress of piping caused by pressure, weight and displacement (in calculating displacement stress, the stress amplification coefficient is not included) is not more than 30% of the allowable stress value of the material at normal temperature and not more than 50 MPa Note: The maximum allowable working pressure of straight pipe and butt welded pipe fitting shall be calculated using equations given in GB/T 20801.3-2020 or determined by type test; that of flange and valve components shall be selected as the rating at normal temperature pressure specified in the corresponding standard. 3.2 lower temperature and lower stress service working conditions that need to meet the following conditions at the same time: a) The maximum working pressure at low temperature is not more than 80% of the maximum allowable working pressure at normal temperatures; b) The sum of axial tensile stress of piping caused by pressure, weight and displacement (in calculating displacement stress, the stress amplification coefficient is not included) is not more than 80% of the allowable stress value of the material at normal temperatures 3.3 electric-resistance welded pipe; ERW continuous butt welded pipe (coil) under pressure, using itself as the current circuit, and heated by resistance 3.4 electric-fusion welded pipe; EFW longitudinally butt-welded pipe on the preformed blank by automatic or manual arc welding 3.5 plate welded pipe electric-fusion welded pipe, with one or two longitudinal straight welds, preformed into a tubular shape from a flat plate

Contents of GB/T 20801.2-2020

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 General requirement 5 Basic principles of material selection 6 Service restrictions of materials 7 Service restrictions of materials at high temperature 8 Service restrictions of materials at low temperature 9 Material marking and inspection certificate Annex A (Normative) Material designation and allowable stress Annex B (Informative) Physical properties of materials Annex C (Informative) Risk-based material design and selection Annex D (Informative) Comparison table of Chinese and foreign material standards and designations Bibliography