GB/T 20801-2020 (GB/T 20801.1~GB/T 20801.6-2020)
GB/T 20801 consists of the following six parts under the general title of Pressure piping code - Industrial piping:
——Part 1: General;
——Part 2: Materials;
——Part 3: Design and calculation;
——Part 4: Fabrication and assembly;
——Part 5: Inspection and testing;
——Part 6: Safeguarding.
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
GB/T 20801 consists of the following six parts under the general title of Pressure piping code - Industrial piping:
——Part 1: General;
——Part 2: Materials;
——Part 3: Design and calculation;
——Part 4: Fabrication and assembly;
——Part 5: Inspection and testing;
——Part 6: Safeguarding.
Pressure piping code - Industrial piping - Part 1: General
1 Scope
1.1 GB/T 20801 specifies the basic requirements for the design, fabrication, assembly, inspection, testing and safeguarding of industrial metal pressure piping.
1.2 This part of GB/T 20801 specifies the basic requirements for pressure piping, such as application scope and piping grading.
1.3 The industrial metal pressure piping (hereinafter referred to as “pressure piping”) in this part includes the pressure piping for process devices, auxiliary devices and utility works within the battery limit.
This part is applicable to the piping with the following conditions:
a) The pressure piping with the maximum working pressure greater than or equal to 0.1MPa (gauge pressure) and a nominal diameter greater than or equal to 50mm, for which the medium may be gas, liquefied gas, steam or flammable, explosive, toxic and corrosive liquid with the maximum working temperature greater than or equal to the standard boiling point. The piping and equipment piping with a nominal diameter less than 150mm and the maximum working pressure less than 1.6MPa (gauge pressure) for conveying non-toxic, nonflammable and non-corrosive gases is excluded.
b) Pressure piping other than those listed in 1.5.
1.4 The exclusion scope of this part is as follows:
a) special requirements for reconstruction, examination, inspection, test, maintenance and repair of in-service pressure piping;
b) piping with a nominal pressure greater than PN420;
c) non-metal piping or lining layers thereof.
1.5 The non-application scope of this part is as follows:
a) piping of military equipment and nuclear facilities;
b) piping of exploration and excavation devices for petroleum, natural gas, terrestrial heat, etc.;
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
3.6
inspection certificate
a form of material quality certificate, which is an inspection document. It is recorded with the inspection result obtained by the following process: independent authorized departments or personnel other than the production department of the manufacturer inspect and test the delivered products in batches (or by sampling) according to the requirements of the standards and the provisions of the contract, and indicate the results on such document
——Part 1: General;
——Part 2: Materials;
——Part 3: Design and calculation;
——Part 4: Fabrication and assembly;
——Part 5: Inspection and testing;
——Part 6: Safeguarding.