GB/T 43403-2023Road vehicles - Trailers up to 3.5t - Control of welded towing brackets for coupling ball after fatigue testing (English PDF)

Foreword

This document is drafted in accordance with GB/T 1.1-2020 "Directives for

standardization - Part 1: Rules for the structure and drafting of standardizing

documents".

This document modifies and adopts ISO 18207:2006 "Road vehicles - Trailers up to 3.5

t - Control of welded towing brackets for coupling ball after fatigue testing".

This document has added a Clause "Terms and definitions".

Compared with ISO 18207:2006, this document has made the following structural

adjustments:

- Merge 7.1.4.5 and 7.1.4.6 of ISO 18207:2006 into 7.1.4.5.

The technical differences between this document and ISO 18207:2006 and their reasons

are as follows:

- Delete Clause 4 of ISO 18207:2006; the contents of this Clause are indicative

provisions;

- Replace ISO 3853 with normatively-referred GB/T 25988 (see Clause 4), to adapt

to China's technical conditions;

- Change the personnel requirements; add normatively-referred GB/T 9445 (see

Clause 5), to comply with China's qualification requirements for practitioners;

- Add the requirement that "When the thickness of paint or coating is greater than or

equal to 50 µm, before testing, it shall verify the sensitivity". Add normatively-

referred GB/T 26951 (see 7.1.4.1), to improve testing sensitivity and defect

detection rate;

- Delete Clause 9 of ISO 18207:2006. The content of this Clause is stipulated as the

content of inspection report. Inspection report is stipulated in relevant documents

in China such as RB/T 214-2017.

This document has made the following editorial changes:

- In order to coordinate with the existing standards, change the name of the standard

to "Road vehicles - Trailers up to 3.5 t - Control of welded towing brackets for

coupling ball after fatigue testing";

- Delete the bibliography.

Attention is drawn to the possibility that some of the elements of this document may be

Road vehicles - Trailers up to 3.5 t - Control of welded

towing brackets for coupling ball after fatigue testing

1 Scope

This document specifies the aim and principles, personnel requirements, choice of

method, testing requirements, and result determination for the control of mechanical

coupling devices between the towing vehicle and the light trailer equipped with

coupling devices that comply with GB/T 25988 after fatigue testing.

This document is applicable to all the components of the mechanical coupling devices

whose failure can cause the fracture of the attachment, manufactured out of steel, forged

steel or cast steel (i.e., generally in ferromagnetic materials).

Note: In the case of use of other materials, the manufacturer will check their compatibility with the

methods of non-destructive testing.

2 Normative references

The contents of the following documents, through normative references in this text,

constitute indispensable provisions of this document. Among them, for dated references,

only the edition corresponding to that date applies to this document. For undated

references, the latest edition (including all amendments) applies to this document.

GB/T 9445 Non-destructive testing - Qualification and certification of NDT

personnel

GB/T 25988 Road vehicles - Towing vehicle coupling device to tow caravans or

light trailers - Mechanical strength test (GB/T 25988-2010, ISO 3583:1994, IDT)

GB/T 26951 Non-destructive testing of welds - Magnetic particle testing

3 Terms and definitions

The terms and definitions defined in GB/T 25988 apply to this document.

4 Aim and principles of controls

The purpose of controls after fatigue testing is to detect the defects caused by the

strength test (according to GB/T 25988), i.e., to distinguish the evolutionary defects

50 µm, before testing, it shall verify the sensitivity of the measuring device. Sensitivity

verification is performed in accordance with the requirements of GB/T 26951.

10 °C~50 °C.