GB/T 11345-2023 Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels and assessment
1 Scope
This document specifies techniques for the manual ultrasonic testing of fusion-welded joints in metallic materials of thickness ≥8 mm which exhibit low ultrasonic attenuation (especially that due to scatter) at object temperatures from 0 °C to 60 °C. It is primarily intended for use on full penetration welded joints where both the welded and parent material are ferritic.
Where material-dependent ultrasonic values are specified in this document, they are based on steels having an ultrasonic sound velocity of (5 920 ± 50) m/s for longitudinal waves and (3 255 ± 30) m/s for transverse waves.
This document specifies four testing levels, each corresponding to a different probability of detection of imperfections. Guidance on the selection of testing levels A, B, and C is given in Annex A.
This document specifies that the requirements of testing level D, which is intended for special applications, be in accordance with general requirements. Testing level D can only be used when defined by specification. This includes tests of metals other than ferritic steel, tests on partial penetration welds, tests with automated equipment, and tests at object temperatures outside the range 0 °C to 60 °C.
This document can be used for the assessment of discontinuities, for acceptance purposes, by either of the following techniques:
a) evaluation based primarily on length and echo amplitude of the discontinuity;
b) evaluation based on characterization and sizing of the discontinuity by probe movement techniques.
2 Normative references
The following referenced documents are indispensable for the application 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 5577 Non-destructive testing - Ultrasonic testing - Vocabulary
Note: GB/T 12604.1-2020 Non-destructive testing - Terminology - Ultrasonic testing (ISO 5577:2017, MOD)
ISO 9712 Non-destructive testing - Qualification and certification of NDT personnel
Note: GB/T 9445-2015 Non-destructive testing - Qualification and certification of NDT personnel (ISO 9712:2012, IDT)
ISO 11666 Non-destructive testing of welds - Ultrasonic testing - Acceptance levels
Note: GB/T 29712-2023 Non-destructive testing of welds - Ultrasonic testing - Acceptance levels (ISO 11666:2018, IDT)
ISO 16810 Non-destructive testing - Ultrasonic testing - General principles
Note: GB/T 39240-2020 Non-destructive testing - Ultrasonic testing - General principles (ISO 16810:2012, MOD)
ISO 16811 Non-destructive testing - Ultrasonic testing - Sensitivity and range setting
Note: GB/T 39242-2020 Non-destructive testing - Ultrasonic testing - Sensitivity and range setting (ISO 16811:2012, MOD)
ISO 16826 Non-destructive testing - Ultrasonic testing - Examination for discontinuities perpendicular to the surface
Note: GB/T 39238-2020 Non-destructive testing - Ultrasonic testing - Examination for discontinuities perpendicular to the surface (ISO 16826:2012, MOD)
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)
ISO 23279 Non-destructive testing of welds - Ultrasonic testing - Characterization of discontinuities in welds
Note: GB/T 29711-2023 Non-destructive testing of welds - Ultrasonic testing - Characterization of discontinuities in welds (ISO 23279:2017, IDT)
ISO 22232
(all parts) Non-destructive testing - Characterization and verification of ultrasonic test equipment
3 Terms and definitions
Foreword II
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 General
6 Information required prior to testing
7 Requirements for personnel and equipment
8 Testing volume
9 Preparation of scanning surfaces
10 Parent metal testing
11 Range and sensitivity setting
12 Testing levels
13 Testing techniques
14 Test report
Annex A (Nominative) Testing levels for various types of welded joints
Bibliography
