GB/T 11345-2023 Active

This document describes the manual ultrasonic testing technology for fusion welded joints of metals with a base material thickness of not less than 8 mm, which exhibit low ultrasonic attenuation (especially low scattering attenuation). During the testing, the temperature of the weld and its base material ranges from 0 °C to 60 °C. This document is mainly applicable to fully penetrated welds where both the base material and the weld are ferritic steels. The ultrasonic characteristics of the materials described in this document are based on a longitudinal wave speed of (5,920±50) m/s and a transverse wave speed of (3,255±30) m/s for steel. This document describes four testing grades, with different detection rates corresponding to different detection grades. Appendix A provides a selection guide for testing grades A, B, and C. This document specifies the general requirements for using testing grade D only in special applications. Testing grade D can only be used when specified in the specification. Special applications include the detection of non-ferritic welds, partially penetrated welds, the detection of welds using automated equipment, and the detection of welds at temperatures outside the range of 0 °C to 60 °C. This document applies to the evaluation or acceptance of discontinuities detected by any of the following techniques: a) evaluation based on the length and echo amplitude of the discontinuities; b) evaluation based on the characteristics and dimensions of the discontinuities obtained using probe movement technology.