GB/T 6402-2024 Method for ultrasonic testing of steel forgings
1 Scope
This document specifies the general requirements, testing equipment, reference block, testing implementation, classification, assessment, record levels and acceptance criteria, as well as test reports for ultrasonic testing of steel forgings.
This document is applicable to the ultrasonic pulse reflection testing of ferritic, martensitic and ferritic-martensitic steel forgings, austenitic and austenitic-ferritic stainless steel forgings, and is also applicable to the ultrasonic testing of forged superalloys and alloy steel cakes. Steel forgings of other organizations can be used as a reference.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 9445 Non-destructive testing- Qualification and certification of personnel
GB/T 2604.1 Non-destructive testing - Terminology - Terms used in ultrasonic testing
GB/T 0737 Non-destructive testing - General terms and definitions
GB/T 3905 Non-destructive testing - Blocks for ultrasonic testing
GB/T 7664.1 Non-destructive testing - Characterization and verification of ultrasonic test equipment - Part 1: Instruments
GB/T 7664.2 Non-destructive testing - Characterization and verification of ultrasonic test equipment - Part 2: Probes
GB/T 39239 Non-destructive testing - Ultrasonic testing - Characterization and sizing of discontinuities
GB/T 39242 Non-destructive testing - Ultrasonic testing - Sensitivity and range setting
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 12604.1 and GB/T 20737 apply.
4 Agreement
The supplier and the purchaser shall agree on one or more of the following relevant ultrasonic testing methods at the time of ordering (if not specified by the purchaser, the testing method shall be chosen by the supplier):
——The testing time (see 5.3);
——Whether it is necessary to submit a written testing procedure approved by the purchaser (see 5.4);
——Whether near-surface testing is required (see 6.2.5);
——Other testing requirements for Type 4 complex shape forgings or complex parts of forgings (see 8.2.3);
——Sensitivity setting method (see 8.3);
——Whether angle-beam probe is required for testing (see 8.3.3);
——Whether the testing scope will employ a raster scanning or a 100% scanning (see 8.6.1);
——Whether special equipment, scanning scope, etc. are required in addition to the requirements specified in Clauses 6 and 8;
——Quantitative method of strip discontinuities (see 10.2);
——Quality level or levels and areas required (see Clause 11);
——The scanning method adopted when manual scanning is not used;
——Whether the presence of the purchaser and/or its agent is required during the testing.
Contents Foreword III 1 Scope 2 Normative references 3 Terms and definitions 4 Agreement 5 General requirements 6 Testing equipment 7 Reference block 8 Testing 9 Classification 10 Assessment of discontinuity 11 Record levels and acceptance criteria 12 Testing reports Annex A (Informative) Maximum testing depth for shear wave circumferential shear wave scanning Annex B (Informative) Method of sensitivity adjustment by workpiece bottom wave Annex C (Informative) Ultrasonic testing of forged round disks Annex D (Informative) Correspondence between DAC (%) amplitude and dB value