GB/T 32957-2016 in English

《GB/T 32957-2016液压和气动系统设备用冷拔或冷轧精密内径无缝钢管》由TC183（全国钢标准化技术委员会）归口，TC183SC1（全国钢标准化技术委员会钢管分会）执行，主管部门为中国钢铁工业协会。

ChinaStandards.net is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.

This standard is developed in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed by China Iron and Steel Association.

This standard is under the jurisdiction of the National Technical Committee on Iron and Steel of Standardization Administration of China (SAC/TC 183).

Contens

Foreword I
1 Scope 1
2 Normative reference 1
3 Classification and code 3
4 Order contents 3
5 Dimension, shape, weight and tolerance 4
6 Technical requirements 8
7 Test method 12
8 Inspection rules 13
9 Packaging, marking and quality certificate 14


Cold-drawn or cold-rolled precision inside diameter seamless
steel tubes for hydraulic and pneumatic system service

1 Scope

This standard specifies the classification and code, ordering content, dimension, shape, weight, tolerance, technical requirements, test methods, inspection rules, packaging, marking and product quality certificates for hydraulic and pneumatic system service.

This standard is applicable to the cold-drawn or cold-rolled precision inside diameter seamless steel tubes for hydraulic and pneumatic system service (hereinafter referred to as steel tubes).

2 Normative reference

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 222 Permissible tolerances for chemical composition of steel products

GB/T 223.5 Steel and iron — Determination of acid-soluble silicon and total silicon content — Reduced molybdosilicate spectrophotometric method

GB/T 223.12 Methods for chemical analysis of iron, steel and alloy — The sodium carbonate separation-diphenyl carbazide photometric method for the determination of chromium content

GB/T 223.23 Iron, steel and alloy — Determination of nickel content — The dimethylglyoxime spectrophotometric method

GB/T 223.26 Iron, steel and alloy — Determination of molybdenum content — The thiocyanate spectrophotometric method

GB/T 223.53 Methods for chemical analysis of iron, steel and alloy — Flame atomic absorption spectrometric method for the determination of copper content
GB/T 223.59 Iron, steel and alloy — Determination of phosphorus content — Bismuth phosphomolybdate blue spectrophotometric method and antimony phosphomolybdate blue spectrophotometric method

GB/T 223.63 Methods for chemical analysis of iron, steel and alloy — The sodium (potassium) periodate photometric method for the determination of manganese content

GB/T 223.68 Methods for chemical analysis of iron, steel and alloy — The potassium iodate titration method after combustion in the pipe furnace for the determination of sulfur content

GB/T 223.69 Iron, steel and alloy — Determination of carbon contents — Gas-volumetric method after combustion in the pipe furnace

GB/T 228.1 Metallic materials — Tensile testing — Part 1: Method of test at room temperature

GB/T 229 Metallic materials — Charpy pendulum impact test method

GB/T 242 Metallic materials — Tube — Drift expanding test

GB/T 246 Metallic materials — Tube — Flattening test

GB/T 699-2015 Quality carbon structure steels

GB/T 1031 Geometrical product specifications (GPS) — Surface texture: Profile method — Surface roughness parameters and their values

GB/T 1591-2008 High strength low alloy structural steels

GB/T 2102 Acceptance, packing, marking and quality certification of steel pipe

GB/T 2975 Steel and steel products — Location and preparation of samples and test pieces for mechanical testing

GB/T 3077-2015 Alloy structure steels

GB/T 4336 Carbon and low-alloy steel — Spark discharge atomic emission spectrometric method (routine method)

GB/T 6394 Determination of estimating the average grain size of metal

GB/T 7735-2004 Steel tubes — The inspection method on eddy current test
GB/T 12606-2016 Automated full peripheral flux leakage testing of seamless and welded (except submerged arc-welded) ferromagnetic steel tubes for the detection of longitudinal and/or transverse imperfections

GB/T 17395 Dimensions, shapes, masses and tolerances of seamless steel tubes

GB/T 20066 Steel and iron — Sampling and preparation of samples for the determination of chemical composition

GB/T 20123 Steel and iron — Determination of total carbon and sulfur content — Infrared absorption method after combustion in an induction furnace (routine method)

GB/T 20125 Low-alloy steel — Determination of multi-element contents — Inductively coupled plasma atomic emission spectrometric method

3 Classification and code

Steel tubes are classified and coded according to delivery state as follows:

a) Cold-drawn or cold-rolled/hard: +C;

b) Cold-drawn or cold-rolled/soft: +LC;

c) Stress-relief annealing after cold-drawn or cold-rolled: +SR;

d) Annealing: +A;

e) Normalizing: +N.

4 Order contents

The contract or order for ordering steel tubes according to this standard shall include but not be limited to the following contents:

a) Standard No.;

b) Product name;

c) Steel designation (quality grade);

d) Dimension and specification;

e) The order quantity (total weight or total length);

f) Delivery state;

g) Manufacturing method;

h) Special requirements.

5 Dimension, shape, weight and tolerance

5.1 Dimension

5.1.1 Steel tubes are usually delivered with inner diameter and wall thickness. If the purchaser requires outer diameter and inner diameter or outer diameter and wall thickness for delivery, it shall be indicated in the contract.

5.1.2 For the inner diameter and wall thickness of steel tubes, the dimensions listed in Table 1 shall be prior. Steel tubes with specifications other than those given in Table 1 may be supplied upon agreement between the supplier and the purchaser.

5.1.3 The tolerances for the inner and outer diameter of cold working (+C, +LC) steel tubes shall meet those specified in Table 1 and Table 2. For the steel tubes in thermal treatment (+SR, +A and +N) status, their tolerances for the inner and outer diameter shall meet those specified in Table 3.

5.1.4 As required by the purchaser and indicated in the contract upon the agreement between the supplier and the purchaser, steel tubes beyond the tolerances specified in Tables 1, 2 and 3 may be supplied.

Foreword I
1 Scope
2 Normative reference
3 Classification and code
4 Order contents
5 Dimension, shape, weight and tolerance
6 Technical requirements
7 Test method
8 Inspection rules
9 Packaging, marking and quality certificate