GB/T 4357-2022Cold-drawn unalloyed steel wire for springs (English PDF)

Foreword

This document was drafted, in accordance with the provisions of GB/T 1.1-2020

"Directives for standardization - Part 1.Rules for the structure and drafting of

standardizing documents".

This document replaces GB/T 4357-2009 "Cold-drawn non-alloy steel wire for springs".

Compared with GB/T 4357-2009, except for structural adjustment and editorial changes,

the main technical changes are as follows.

a) ADD the normative references (see Chapter 2; Chapter 2 of the 2009 edition);

b) ADD the term "patented" and its definition. DELETE the terms "cold-drawn non-

alloy steel wire for spring" and "ring" and their definition; CHANGE the

definition of other terms (see Chapter 3; Chapter 3 of 2009 edition);

c) CHANGE the Table 1 and order content (see Table 1; Chapters 4 and 5 of the 2009

edition);

d) CHANGE the technical requirements for wire rods (see 7.1.1; 7.1.2 and Table 5

of the 2009 edition);

e) ADD the area reduction index (see Table 6); CHANGE some torsional

performance indexes (see Table 6; Table 8 of 2009 edition), as well as some

strength indexes in the range of 0.40 mm ~ 0.48 mm (see Table 6; Table 8 of the

2009 edition);

f) CHANGE the allowable fluctuation range of the tensile strength of the same coil

of steel wire (see Table 7; 7.4.2 of the 2009 edition);

g) ADD the inspection method for the pitch (see 8.1.4);

h) ADD the inspection method for aluminum content, in zinc-aluminum alloy plating

(see 8.2.1);

i) CHANGE the "nominal diameter" on which the tensile strength is based, into

"measured diameter" (see 8.4; 7.4.1 of the 2009 edition);

j) CHANGE the "Summary of inspection items, applicability, requirements,

sampling inspection proportion, test methods, technical requirements" (see Table

8; Table 9 of the 2009 edition);

k) ADD the transport and storage requirements (see 10.1; 10.1 of the 2009 edition);

l) ADD the Appendix C, to provide guidance and suggestions for the selection of

steel wires.

This document modifies and adopts ISO 8458-2.2002 "Steel wire for mechanical

springs - Part 2.Patented cold-drawn non-alloy steel wire".

Compared with ISO 8458-2.2002, this document has many adjustments in structure.

See Appendix A, for a comparison of structure numbering changes between the two

documents.

Compared with ISO 8458-2.2002, this document has many technical differences, which

are marked by a vertical single line (|) in the outer margin of the clauses involved. See

Appendix B, for these technical differences and their reasons.

Please note that some content of this document may be patented. The issuing agency of

this document assumes no responsibility for identifying patents.

This document was proposed by China Iron and Steel Association.

This document shall be under the jurisdiction of the National Steel Standardization

Technical Committee (SAC/TC 183).

This document was first published in 1984; revised for the first time in 1989; revised

for the second time in 2009.This is the third revision.

1 Scope

This document specifies the classification and marking, order content, size and shape

requirements, technical requirements, test methods, inspection rules, packaging,

transportation, storage, marking, quality certificates for the manufacture of cold-drawn

non-alloy steel wire for springs.

2 Normative references

The provisions in following documents become the provisions of this Standard through

reference in this Standard. For the dated documents, only the versions with the dates

indicated are applicable to this document; for the undated documents, only the latest

version (including all the amendments) is applicable to this standard.

GB/T 222 Permissible tolerances for chemical composition of steel products

GB/T 224 Determination of the depth of decarburization of steels (GB/T 224-2019,

ISO 3887.2017, MOD)

GB/T 228.1 Metallic materials - Tensile testing - Part 1.Method of test at room

temperature (GB/T 228.1-2010, ISO 6892-1.2009, MOD)

GB/T 239.1 Metallic materials - Wire - Part 1.Simple torsion test (GB/T 239.1-

2012, ISO 7800.2003, MOD)

GB/T 341 Steel wire - Classification and terminology

GB/T 342-2017 Dimension, shape, mass and tolerance of cold-drawn round square

and hexagonal steel wires (ISO 22034-2.2016, NEQ)

GB/T 1839 Test method for gravimetric determination of the mass per unit area of

galvanized coatings on steel products (GB/T 1839-2008, ISO 1460.1992, MOD)

3 Terms and definitions

The terms and definitions, which are defined in GB/T 341, as well as the following

terms and definitions, apply to this document.

3.1

Patented

A heat treatment method, which places the medium carbon steel or high carbon steel,

that was heated for austenitizing, in a hot bath of appropriate temperature (such as

lead bath, salt bath, water bath, etc.) OR in a forced air flow (such as controlled air

cooling after rolling in a steel mill), for cooling purposes, to obtain sorbite or sorbite-

based metallography.

[Source. 5.50 of GB/T 7232-2012, and 3.3.14 of GB/T 341-2008, with modifications]

3.2

Static load

The constant load, OR the load, which changes but whose design stress does not

exceed 0.1 times the fatigue strength, OR the load whose design stress exceeds 0.1

times the fatigue strength but total number of cycles does not reach 10000, as

undertaken by the spring.

[Source. GB/T 23935-2009, 5.1.1, with modifications]

4 Classification and marking

Corresponding to the stress level of the spring, the steel wire can be divided into three

strength grades. low tensile strength (L), medium tensile strength (M), high tensile

strength (H).

5 Order contents

The order contracts under this document shall contain the following requirements.

a) This document number;

b) Nominal diameter of steel wire;

c) Quantity.

6 Dimensions and shape requirements

The allowable deviation of the diameter of the coiled steel wire shall meet the

requirements of Table 2.The allowable deviation of the diameter of the straight steel

wire shall meet the requirements of Table 3.

7 Technical requirements

The chemical composition (melting analysis) of the steel shall comply with the

requirements in Table 4.The allowable deviation of the chemical composition of the

finished steel wire shall comply with the provisions of GB/T 222.

Phosphating is a common plating. Other coatings can be negotiated.

The plated steel wire can be galvanized, plated with zinc-aluminum alloy or copper;

OR other plating can be negotiated, between the supplier and the buyer.

8 Test methods

Steel wire's diameter. Use an outer micrometer to measure on any cross-section;

take the arithmetic mean of two values, in the mutually perpendicular directions.

Out-of-roundness of steel wire. The difference, between the largest diameter and

the smallest diameter, which is measured on the same cross-section.

9 Inspection rules

Unless there is a special agreement between the supplier and the buyer, all tests shall

be carried out at the supplier's premises.

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