GB/T 26951-2011 in English

《GB/T 26951-2011焊缝无损检测 磁粉检测》由TC55（全国焊接标准化技术委员会）归口，TC55SC3（全国焊接标准化技术委员会焊缝试验和检验分会）执行，主管部门为国家标准化管理委员会。

Non-destructive testing of welds — Magnetic particle testing

1 Scope

This standard specifies techniques for detection of surface imperfections in welds in ferromagnetic materials, including the heat affected zones, by means of magnetic particle testing. Variations in the basic techniques that will provide a higher or lower test sensitivity, are described in Annex A.

This standard is suitable for most welding processes and joint configurations.

This standard does not specify acceptance levels of the indications. Further information on acceptance levels for indications may be found in GB/T 26952 or in product or application standards.

2 Normative References

The following referenced documents are indispensable for the purpose 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 5097 Non-destructive testing — Penetrant testing and magnetic particle testing — Viewing conditions (GB/T 5097-2005, ISO 3059:2001, IDT)
GB/T 5616 Non-destructive testing — Guidelines for application
GB/T 9445 Non-destructive testing — Qualification and certification of personnel (GB/T 9445-2008, ISO 9712:2005, IDT)
GB/T 12604.5 Non-destructive Testing — Terminology — Terms Used in Magnetic Particle Testing
GB/T 15822.2 Non-destructive testing — Magnetic particle testing — Part 2: Detection media
GB/T 15822.3 Non-destructive testing — Magnetic particle testing — Part 3: Equipment (GB/T 15822.3-2005, ISO 9934-3:2002, IDT)
GB/T 20737 Non-destructive testing — General terms and definitions (GB/T 20737-2006, ISO/TS 18173:2005, IDT)
GB/T 23907 Non-destructive Testing — Shims for Magnetic Particle Testing
GB/T 26952 Non-destructive testing of welds — Magnetic particle testing of welds — Acceptance levels (GB/T 26952-2011, ISO 23278:2006, MOD)


3 Terms and definitions

For the purpose of this document, the terms and definitions given in GB/T 12604.5 and GB/T 20737 apply.

4 Safety precautions

National and local safety and environmental protection regulations shall be observed at all times. Special consideration shall be given to toxic, inflammable and volatile materials, electrical safety and unfiltered UV radiation.

5 General

5.1 Information required prior to testing

Prior to testing, the following items shall be specified (where applicable):

a) specific test procedure (see GB/T 5616);

b) certification requirements for NDT personnel;

c) extent of coverage;

d) state of manufacture;

e) testing techniques to be used;

f) overall performance test;

g) demagnetization requirements;

h) acceptance level;

i) action necessary for unacceptable indications.

5.2 Additional pre-test information

Prior to testing, the following additional information may also be required:

a) type and designation of the parent and weld materials;

b) welding process;

c) location and extent of welds to be tested;

Foreword I
1 Scope
2 Normative References
3 Terms and definitions
4 Safety precautions
5 General
5.1 Information required prior to testing
5.2 Additional pre-test information
5.3 Personnel qualification
5.4 Surface conditions and preparation
5.5 Magnetizing
5.6 Application techniques
5.7 Detection media
5.8 Viewing conditions
5.9 Application of detection media
5.10 Overall performance test
5.11 False indications
5.12 Recording of indications
5.13 Demagetization
5.14 Test report
Annex A (Informative) Variables affecting the sensitivity of magnetic particle testing
Annex B (Normative) Magnetic cross coil technology
Annex C (Normative) Overall performance test of system sensitivity with test pieces