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This standard replaces GB/T 12771-2000 “Welded Stainless Steel Pipes for Liquid Delivery”. There are some significant changes in this national standard compared with GB/T 12771-2000 in the following aspects:
--Application scope is modified;
--The universal standard of welded steel pipe is directly applicable to dimensions;
--Steel grade and chemical composition are modified;
--Permissible deviation of steel pipe dimension is modified;
--Non-circularity provision of steel pipe is added;
--Weld manufacturing method is specified;
--Flattening test of steel pipe whose external diameter is not less than 200mm is modified;
--Transverse bending test of weld of steel pipe whose external diameter is not less than 219mm is in added;
--Reinforcement provision of weld is modified;
--Expansion test is cancelled.
This national standard is proposed by China Iron & Steel Association.
This national standard is under jurisdiction of China Steel Standardization Technical Committee.
Chief drafting organizations: Taiyuan Iron and Steel (Group) Stainless Steel pipe Products Co., Ltd., Zhejiang Jiuli Hi-tech Metals Co., Ltd. and Jiang Su Wujin Stainless Steel Pipe Group Co., Ltd.
Chief drafting staffs: LI Changyi, LU Fenghui, TIAN Xiaoqing, SHAO Yu, SONG Jianxin, YU Yuan and GONG Jianzhong.
This national standard replaces the previous versions:
--GB/T 12771-1991, GB/T 12771-2000.
Welded Stainless Steel Pipes for Liquid Delivery
1 Scope
This national standard specifies classification and code name, dimension, shape, weight, technical requirements, test methods, test rules, packaging, mark and quality certificate of steel pipes for liquid delivery.
This national standard is applicable to the anticorrosion welded stainless steel pipes for liquid delivery (hereinafter referred to as “steel pipe”).
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this national standard. For dated reference, subsequent amendments (excluding amending error in the text) to, or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For undated references, the latest edition of the documents referred to applies.
GB/T 223.10 Chemical analysis method for steel and alloy: the chrome azurol s photometry for the determination of aluminum content after separation by cupferron
GB/T 223.11 Chemical analysis method for steel and alloy: ammonium persulfate oxidation volumetric method for the determination of chromium content
GB/T 223.16 Chemical analysis method for steel and alloy: chromotropic acid photometry for the determination of titanium content
GB/T 223.25 Chemical analysis method for steel and alloy: dimethylglyoxime-gravimetric method for the determination of nickel content
GB/T 223.28 Chemical analysis method for steel and alloy: α-benzoin oxime gravimetric method for the determination of molybdenum content
GB/T 223.30 Chemical analysis method for steel and alloy: arsenazo Ⅲ spectrophotometric method for the determination of zirconium content after separation by p-bromomandelic acid
GB/T 223.37 Chemical analysis method for steel and alloy: indophenol blue photometry for the determination of nitrogen content after separation by distillation
GB/T 223.40 Steel and alloy: sulphur phenol spectrophotometry for the determination of niobium content
GB/T 223.60 Chemical analysis method for steel and alloy: perchloric acid dehydration gravimetric method for the determination of silicon content
GB/T 223.62 Chemical analysis method for steel and alloy: butyl acetate extraction-photometric method for the determination of phosphorus content
GB/T 223.63 Chemical analysis method for steel and alloy: heavy sodium iodate (kalium iodate) photometry for the determination of manganese content
GB/T 223.68 Chemical analysis method for steel and alloy: kalium iodate titrimetric method for the determination of sulfur content after combustion in the tubular furnace
GB/T 228 Metallic Materials: Ttensile test at ambient temperature (GB/T 228- 2002, eqv ISO 6892: 1998)
GB/T 232 Metal materials: bending test method (GB/T 232-1999, eqv ISO 7438: 1985)
GB/T 241 Metal pipe: hydraulic test method
GB/T 245 Metal pipe: flange test method (GB/T 245-1997, eqv ISO 8494: 1986)
GB/T 246 Metal pipe: flattening test method (GB/T 246-2007, ISO 8492: 1998, IDT)
GB/T 2102 Acceptance inspection, packaging, mark and quality certificate of steel pipe
GB/T 2650 Soldered joint impact test method
GB/T 2975 Mechanical test of steel and steel products: sampling location and specimen preparation (GB/T 2975-1998, eqv ISO 377: 1997)
GB 3323 Methods for radiographic inspection and classification of radiographs for fusion welded butt joints in steel
GB/T 4334.5 Stainless steel-sulfuric acid-copper sulfate corrosion test method
GB/T 6394 Average particle dimension determination method for metal
GB/T 7735 Eddy current inspection method for steel pipes (GB/T 7735-2004, ISO 9304: 1989, MOD)
GB/T 11170 Photoemission spectral analysis method for stainless steel
GB/T 20066 Specimen sampling and sampling method for the determination of chemical composition in steel and iron (GB/T 20066-2006, ISO 14284: 1996, IDT)
GB/T 20123 Infrared absorption method (conventional method) for the determination of total carbon and sulfur content of steel after combustion in the Efco-Northrup furnace (GB/T 20123-2006, ISO 15350: 2000, IDT)
GB/T 20124 Inert gases heat of melting conductance method (conventional method) for the determination of nitrogen content of steel (GB/T 20124-2006, ISO 15351: 1999, IDT)
GB/T 21835 Dimension and unit weight of welded steel pipe (GB/T 21835-2008, ISO 1127: 1992, ISO 4200: 1991, NEQ)
3. Classification and Code Name
3.1 Steel pipe is divided into the following six categories according to manufacture categories:
TypeⅠ--Steel pipe is made according to bifacial automatic welding procedure, and radiographic inspection is adopted for the 100% overall length of weld.
Type Ⅱ--Steel pipe is made according to pedion automatic welding procedure, and radiographic inspection is adopted for the overall length of weld.
Type Ⅲ--Steel pipe is made according to bifacial automatic welding procedure, and radiographic inspection is adopted for partial length of weld.
Type Ⅳ--Steel pipe is made according to pedion automatic welding procedure, and radiographic inspection is adopted for partial length of weld.
Type Ⅴ--Steel pipe is made according to bifacial automatic welding procedure, and radiographic inspection is not adopted for the weld.
Type Ⅵ--Steel pipe is made according to pedion automatic welding procedure, and radiographic inspection is not adopted for the weld.
3.2 Steel pipe is divided into the following four categories according to its supply situation:
a) As-welded condition (H);
b) Heat treatment condition (T);
c) Cold drawing (rolling) condition (WC);
d) Grinding (polishing) condition (SP).
4. Order Content
At least the following contents shall be composed in the steel pipe-purchasing contract or order sheet based on this standard:
a) Standard number;
b) Product name;
c) Steel grade;
d) Dimension (external diameter × wall thickness, in: mm);
e) Order quantity (Total Weight or total length);
f) Delivery state;
g) Manufacture category;
h) Other special requirements.
5 Dimension and Unit Weight
5.1 Outside Diameter and Wall Thickness
External diameter (D) and wall thickness (S) of steel pipe shall meet the provisions of “GB/T 21835”. According to the requirements of buyer and through the mutual negotiation of both buyer and seller, steel pipe with other external diameter and wall thickness can be supplied.
5.2 Permissible Deviation of External Diameter and Wall Thickness
Permissible deviation of external diameter and wall thickness of steel pipes shall meet the provisions of Table 1 and Table 2. According to the requirements of the buyer and through the mutual negotiation of the supplier and the buyer, other steel pipes within the dimension permissible deviation and excluded specified in Table 1 and Table 2 may be supplied. All these shall be indicated in the contract.
If the permissible deviation of steel pipe dimension is not indicated in the contract, the permissible deviation of external diameter and wall thickness of steel pipe shall be delivered according to ordinary grade.