Non-Destructive Testing – Magnetic Particle Testing of Welds
1 Scope
This standard specifies technology and acceptance level for surface imperfection of ferromagnetic material weld (including heat-affected zone) with magnetic particle testing method.
Appendix A describes factors providing related basic technologies for higher or lower test sensitivity.
Appendix B recommends indicated acceptance level, of which more information may be found in the products or the applicable standards.
Basic rules ought to be followed when using non-destructive testing specified in GB/T 5616 shall be applicable to this standard.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections), or revisions, of any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to 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 9445-2005, ISO 9712: 1999, IDT)
GB/T 12604.5 Non-Destructive Testing - Terminology-Terms used in Magnetic Particle Testing1)
GB/T 15822.3 Non-Destructive Testing - Magnetic Particle Testing - Part 3: Equipment (GB/T 15822.3-2005, ISO 9934-3: 2002, IDT)
JB/T 6063 Non-Destructive Testing - Materials for Magnetic Particle Testing
JB/T 6065 Non-Destructive Testing - Shims for Magnetic Particle Testing
3 Terms and Definitions
For the purposes of this standard, the terms and definitions given in GB/T 12604.5 and the following apply.
3.1 Linear indication
Indication with length of larger than three times the width
3.2 Non-linear indication
Indication with length of less than or equal to three times the width
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, explosive materials, electrical safety and unfiltered ultraviolet radiation.
5 General
5.1 Information Required prior to Testing
Prior to testing, the following item shall be specified (where applicable):
a) Special test procedure (it shall comply with requirements of 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) Any demagnetization;
h) Acceptance level;
i) Action necessary for unacceptable indications.
5.2 Additional Pre-test Information
Prior to testing, the following additional information can 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;
d) Joint preparation and dimensions;
e) Location and extent of any repair;
f) Post-weld treatment (if requires);
g) Surface condition
Operators may ask for further information that could be helpful in determining the nature of any indications detected.
5.3 Personnel Qualification
Magnetic particle testing of welds and the evaluation of results for final acceptance shall be performed by qualified and capable personnel. It is recommended that personnel be qualified in accordance with GB/T 9445 or an equivalent standard, laws and regulations at an appropriate level in the relevant industry sector.
5.4 Surface Conditions and Preparation
Areas to be tested shall be free from scale, oil, grease, weld spatter, machining marks, dirt, heavy and loose paint and any other foreign matter that can affect the sensitivity of the test method.
It may be necessary to improve the surface condition, e.g., by use of abrasive paper or local grinding to permit accurate interpretation of indications.
Foreword II
1 Scope
2 Normative references
3 Terminologies and definitions
4 Safety caution
5 General provisions
5.1 Information required before testing
5.2 Additional information before testing
5.3 Personnel qualification
5.4 Surface condition and preparation
5.5 Magnetization
5.6 Applied technology
5.7 Testing media
5.8 Observation condition
5.9 Application of testing media
5.10 Combination property test
5.11 False indications
5.12 Record for indication
5.13 Demagnetization
5.14 Testing report
Appendix A (Informative) Factors Influencing the Sensitivity of Magnetic Particle Testing
A.1 Surface condition and preparation
A.2 Characteristics of magnetized equipment
A.3 Magnetic field intensity and magnetic permeability
A.4 Testing media
Appendix B (Normative) Acceptance Level
B.1 Brief introduction
B.2 Testing parameter
B.3 Acceptance level
Appendix C (Normative) Crossed Yoke Technology
C.1 Brief introduction
C.2 Equipment
C.3 Testing
Appendix D (Normative) Combination Property Test for System Sensitivity with Test Block
D.1 Brief introduction
D.2 Adoption principle for the test block
D.3 Method of application for the test block
D.4 Notices
