GB/T 2970-2026 Method for ultrasonic testing of thick steel plates English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 2970-2026
Method for ultrasonic testing of thick steel plates
厚钢板超声检测方法
Issue date: 2026-06-27 Implementation date: 2027-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 General requirements
5 Reference specimens
6 Testing instruments and equipment
7 Testing conditions and methods
8 Defect measurement and evaluation
9 Quality grades of steel plates
10 Test report
Annex A (normative) Method for shear wave oblique incidence testing of steel plates
Annex B (normative) Performance requirements for twin-crystal straight beam probes
Ultrasonic testing method for thick steel plates
1 Scope
This document specifies the general requirements, reference specimens, testing instruments and equipment, testing conditions and methods, defect measurement and evaluation, quality grades of steel plates, and test reports for ultrasonic testing of thick steel plates.
This document is applicable to piezoelectric and electromagnetic ultrasonic manual and automatic testing of steel plates with a thickness of not less than 5 mm, used for pressure components, bridges, buildings, shipbuilding, steel structures, pipelines and other applications.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 8651, Method for ultrasonic plate wave inspection of metal sheets
GB/T 9445, Non-destructive testing — Qualification and certification of personnel
GB/T 11259, Non-destructive testing — Practice for fabrication and control of steel reference blocks used in ultrasonic testing
GB/T 12604.1, Non-destructive testing — Terminology — Ultrasonic testing
GB/T 27664.1, Non-destructive testing instruments — Performance and verification of ultrasonic testing equipment — Part 1: Instruments
JJG 746, Ultrasonic flaw detectors
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 12604.1, as well as the following, apply.
3.1 piezoelectric ultrasonic testing
Ultrasonic testing that uses the piezoelectric effect to generate and receive ultrasonic waves.
3.2 electromagnetic ultrasonic testing
Ultrasonic testing that uses electromagnetic acoustic transducers (EMATs) as the excitation and receiving core components for ultrasonic waves.
3.3 reference plate
A steel plate with acoustic properties similar to the steel plate under inspection and containing reference reflectors, used to confirm the detectability of the testing system.
4 General requirements
4.1 The surface of the steel plate under inspection shall be flat, smooth and of uniform thickness, free from droplets, oil stains, corrosion and other contaminants that may affect the testing.
4.2 The internal structure of the steel plate under inspection shall not contain interfering factors that may affect the testing.
4.3 The testing site shall be kept away from strong light, strong magnetic fields, strong vibration, corrosive gases, severe dust and other factors that may affect the stability of the ultrasonic testing equipment and the reliable observation of the testing personnel.
4.4 Personnel engaged in ultrasonic testing of steel plates shall be trained and qualified in accordance with GB/T 9445 or equivalent standards. Testing personnel shall be familiar with steel plate manufacturing processes, equipment performance, standards, etc., and shall be authorised by the employer.
4.5 The testing technique shall employ piezoelectric ultrasonic or electromagnetic ultrasonic testing, with manual or automatic scanning methods. The ultrasonic wave modes to be used shall be straight-beam longitudinal waves, shear waves and plate waves. When shear wave oblique incidence and plate wave testing are used as a supplement to straight-beam testing, the supplier and the purchaser shall agree upon this at the time of ordering.
4.6 The couplant used for actual steel plate testing shall be the same as that used for equipment calibration. The couplant may be water, oil or other media.
4.7 When the steel plate temperature exceeds 50 °C, process validation shall be carried out. When electromagnetic ultrasonic testing is used, the temperature of the steel plate under inspection shall be below the Curie point temperature of the material.
5 Reference specimens
5.1 The fabrication of reference specimens shall comply with the requirements of GB/T 11259. The material and acoustic properties of the reference specimen shall be the same as or similar to those of the steel plate under inspection (the difference in acoustic attenuation shall be within ±25 %), and there shall be no defects that may affect the testing in its interior.
5.2 When using piezoelectric ultrasonic twin-crystal straight beam probes for testing steel plates with a thickness not exceeding 20 mm, the reference specimen shall be as shown in Figure 1, with a surface roughness not exceeding 3.2 μm. When using electromagnetic ultrasonic testing for steel plates with a thickness not exceeding 20 mm, a certain number of flat-bottomed holes with a diameter of 5 mm and a hole depth of 1/2 of the plate thickness shall be designed and machined into the reference specimen. Other types and equivalent reference specimens may also be used by agreement between the relevant parties.
Note: The reference specimen type for steel plates with a thickness not exceeding 20 mm is CB Type I.
Standard
GB/T 2970-2026 Method for ultrasonic testing of thick steel plates (English)
Standard No.
GB/T 2970-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
10500 words
Translation Price(USD)
315.0
Implemented on
2027-2-1
Delivery
via email in 1~5 business day
Detail of GB/T 2970-2026
Standard No.
GB/T 2970-2026
English Name
Method for ultrasonic testing of thick steel plates
GB/T 2970-2026 Method for ultrasonic testing of thick steel plates English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 2970-2026
Method for ultrasonic testing of thick steel plates
厚钢板超声检测方法
Issue date: 2026-06-27 Implementation date: 2027-05-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 General requirements
5 Reference specimens
6 Testing instruments and equipment
7 Testing conditions and methods
8 Defect measurement and evaluation
9 Quality grades of steel plates
10 Test report
Annex A (normative) Method for shear wave oblique incidence testing of steel plates
Annex B (normative) Performance requirements for twin-crystal straight beam probes
Ultrasonic testing method for thick steel plates
1 Scope
This document specifies the general requirements, reference specimens, testing instruments and equipment, testing conditions and methods, defect measurement and evaluation, quality grades of steel plates, and test reports for ultrasonic testing of thick steel plates.
This document is applicable to piezoelectric and electromagnetic ultrasonic manual and automatic testing of steel plates with a thickness of not less than 5 mm, used for pressure components, bridges, buildings, shipbuilding, steel structures, pipelines and other applications.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 8651, Method for ultrasonic plate wave inspection of metal sheets
GB/T 9445, Non-destructive testing — Qualification and certification of personnel
GB/T 11259, Non-destructive testing — Practice for fabrication and control of steel reference blocks used in ultrasonic testing
GB/T 12604.1, Non-destructive testing — Terminology — Ultrasonic testing
GB/T 27664.1, Non-destructive testing instruments — Performance and verification of ultrasonic testing equipment — Part 1: Instruments
JJG 746, Ultrasonic flaw detectors
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 12604.1, as well as the following, apply.
3.1 piezoelectric ultrasonic testing
Ultrasonic testing that uses the piezoelectric effect to generate and receive ultrasonic waves.
3.2 electromagnetic ultrasonic testing
Ultrasonic testing that uses electromagnetic acoustic transducers (EMATs) as the excitation and receiving core components for ultrasonic waves.
3.3 reference plate
A steel plate with acoustic properties similar to the steel plate under inspection and containing reference reflectors, used to confirm the detectability of the testing system.
4 General requirements
4.1 The surface of the steel plate under inspection shall be flat, smooth and of uniform thickness, free from droplets, oil stains, corrosion and other contaminants that may affect the testing.
4.2 The internal structure of the steel plate under inspection shall not contain interfering factors that may affect the testing.
4.3 The testing site shall be kept away from strong light, strong magnetic fields, strong vibration, corrosive gases, severe dust and other factors that may affect the stability of the ultrasonic testing equipment and the reliable observation of the testing personnel.
4.4 Personnel engaged in ultrasonic testing of steel plates shall be trained and qualified in accordance with GB/T 9445 or equivalent standards. Testing personnel shall be familiar with steel plate manufacturing processes, equipment performance, standards, etc., and shall be authorised by the employer.
4.5 The testing technique shall employ piezoelectric ultrasonic or electromagnetic ultrasonic testing, with manual or automatic scanning methods. The ultrasonic wave modes to be used shall be straight-beam longitudinal waves, shear waves and plate waves. When shear wave oblique incidence and plate wave testing are used as a supplement to straight-beam testing, the supplier and the purchaser shall agree upon this at the time of ordering.
4.6 The couplant used for actual steel plate testing shall be the same as that used for equipment calibration. The couplant may be water, oil or other media.
4.7 When the steel plate temperature exceeds 50 °C, process validation shall be carried out. When electromagnetic ultrasonic testing is used, the temperature of the steel plate under inspection shall be below the Curie point temperature of the material.
5 Reference specimens
5.1 The fabrication of reference specimens shall comply with the requirements of GB/T 11259. The material and acoustic properties of the reference specimen shall be the same as or similar to those of the steel plate under inspection (the difference in acoustic attenuation shall be within ±25 %), and there shall be no defects that may affect the testing in its interior.
5.2 When using piezoelectric ultrasonic twin-crystal straight beam probes for testing steel plates with a thickness not exceeding 20 mm, the reference specimen shall be as shown in Figure 1, with a surface roughness not exceeding 3.2 μm. When using electromagnetic ultrasonic testing for steel plates with a thickness not exceeding 20 mm, a certain number of flat-bottomed holes with a diameter of 5 mm and a hole depth of 1/2 of the plate thickness shall be designed and machined into the reference specimen. Other types and equivalent reference specimens may also be used by agreement between the relevant parties.
Note: The reference specimen type for steel plates with a thickness not exceeding 20 mm is CB Type I.
