GB/T 26951-2025 Non-destructive testing of welds - Magnetic particle testing
1 Scope
This document specifies techniques for detection of surface imperfections in welds in ferromagnetic materials, including the heat affected zones, by means of magnetic particle testing. The techniques are suitable for most welding processes and joint configurations. Variations in the basic techniques that will provide a higher or lower test sensitivity are described in Annex A.
This document does not specify acceptance levels of the indications. Further information on acceptance levels for indications may be found in ISO 23278 or in product or application standards.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.
ISO 3059 Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions
Note: GB/T 5097-2020, Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions (ISO 3059:2012, IDT)
ISO 9934-1:2016 Non-destructive testing -Magnetic particle testing - Part 1: General principles
Note: GB/T 15822.1-2024, Non-destructive testing - Magnetic particle testing - Part 1: General principles (ISO 9934-1:2016, IDT)
ISO 9934-2 Non-destructive testing - Magnetic particle testing - Part 2: Detection media
Note: GB/T 15822.2-2024, Non-destructive testing - Magnetic particle testing - Part 2: Detection media (ISO 9934-2:2015, IDT)
ISO 9934-3 Non-destructive testing - Magnetic particle testing - Part 3: Equipment
Note: GB/T 15822.3-2024, Non-destructive testing - Magnetic particle testing - Part 3: Equipment (ISO 9934-3:2015, IDT)
ISO 12707 Non-destructive testing - Magnetic particle testing - Vocabulary
Note: GB/T 12604.5-2020, Non-destructive testing-Terminology - Magnetic particle testing (ISO 12707:2016, IDT)
ISO 17635 Non-destructive testing of welds - General rules for metallic materials
Note: GB/T 34628-2017, Non-destructive testing of welds - General rules for metallic materials (ISO 17635:2016, IDT)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12707 and ISO 17635 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
- IEC Electropedia: available at http://www.electropedia.org/
- ISO Online browsing platform: available at http://www.iso.org/obp
4 Safety precautions
Special consideration shall be given to toxic, inflammable and/or volatile materials, electrical safety and unfiltered UV radiation.
Magnetic particle testing often creates high magnetic fields close to the object under test and the magnetising equipment. Items sensitive to these fields should be excluded from such areas.
Contents
Foreword I
1 Scope
2 Normative references
3 Terms and definitions
4 Safety precautions
5 General
Annex A (Informative) Variables affecting the sensitivity of magnetic particle testing
Annex NA (Informative) Cross Yoke Technique
Bibliography
Standard
GB/T 26951-2025 Non-destructive testing of welds - Magnetic particle testing (English Version)
Standard No.
GB/T 26951-2025
Status
to be valid
Language
English
File Format
PDF
Word Count
10500 words
Price(USD)
210.0
Implemented on
2026-2-1
Delivery
via email in 1 business day
Detail of GB/T 26951-2025
Standard No.
GB/T 26951-2025
English Name
Non-destructive testing of welds - Magnetic particle testing
GB/T 26951-2025 Non-destructive testing of welds - Magnetic particle testing
1 Scope
This document specifies techniques for detection of surface imperfections in welds in ferromagnetic materials, including the heat affected zones, by means of magnetic particle testing. The techniques are suitable for most welding processes and joint configurations. Variations in the basic techniques that will provide a higher or lower test sensitivity are described in Annex A.
This document does not specify acceptance levels of the indications. Further information on acceptance levels for indications may be found in ISO 23278 or in product or application standards.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.
ISO 3059 Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions
Note: GB/T 5097-2020, Non-destructive testing - Penetrant testing and magnetic particle testing - Viewing conditions (ISO 3059:2012, IDT)
ISO 9934-1:2016 Non-destructive testing -Magnetic particle testing - Part 1: General principles
Note: GB/T 15822.1-2024, Non-destructive testing - Magnetic particle testing - Part 1: General principles (ISO 9934-1:2016, IDT)
ISO 9934-2 Non-destructive testing - Magnetic particle testing - Part 2: Detection media
Note: GB/T 15822.2-2024, Non-destructive testing - Magnetic particle testing - Part 2: Detection media (ISO 9934-2:2015, IDT)
ISO 9934-3 Non-destructive testing - Magnetic particle testing - Part 3: Equipment
Note: GB/T 15822.3-2024, Non-destructive testing - Magnetic particle testing - Part 3: Equipment (ISO 9934-3:2015, IDT)
ISO 12707 Non-destructive testing - Magnetic particle testing - Vocabulary
Note: GB/T 12604.5-2020, Non-destructive testing-Terminology - Magnetic particle testing (ISO 12707:2016, IDT)
ISO 17635 Non-destructive testing of welds - General rules for metallic materials
Note: GB/T 34628-2017, Non-destructive testing of welds - General rules for metallic materials (ISO 17635:2016, IDT)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12707 and ISO 17635 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
- IEC Electropedia: available at http://www.electropedia.org/
- ISO Online browsing platform: available at http://www.iso.org/obp
4 Safety precautions
Special consideration shall be given to toxic, inflammable and/or volatile materials, electrical safety and unfiltered UV radiation.
Magnetic particle testing often creates high magnetic fields close to the object under test and the magnetising equipment. Items sensitive to these fields should be excluded from such areas.
Contents of GB/T 26951-2025
Contents
Foreword I
1 Scope
2 Normative references
3 Terms and definitions
4 Safety precautions
5 General
Annex A (Informative) Variables affecting the sensitivity of magnetic particle testing
Annex NA (Informative) Cross Yoke Technique
Bibliography