GB/T 41115-2021 Active National standards

GB/T 41115-2021 Non-destructive testing of welds—Ultrasonic testing—Use of time-of-flight diffraction technique (TOFD)

Publish Date: 2021-12-31 Implement Date: 2022-07-01 For services related to genuine standard inquiry, procurement, translation, and other related services in China, please Contact Us

Basic Information

Standard Code: GB/T 41115-2021

Standard Type: National standards

Standard Status: Active

is_force_gb: no

CCS Name: Welding and cutting

ICS Name: \nWelding joints

Publish Date: 2021-12-31

Implement Date: 2022-07-01

Pages: 41 pages

Scope

This document specifies the application of the semi-automatic or fully automatic ultrasonic time-of-flight diffraction (TOFD) technology for fusion welded joints of metal materials with a thickness of not less than 6 mm.
This document is applicable to fully penetrated welded joints of simple geometries in plates, pipes, and containers, where both the weld metal and the base metal are low-carbon steel or low-alloy steel. Under appropriate conditions, TOFD can also be used for other materials with low ultrasonic attenuation (especially scattering attenuation).
This document provides relevant provisions for TOFD applications under the conditions that the longitudinal wave sound velocity of the material is (5 920±50) m/s and the transverse wave sound velocity is (3 255±30) m/s. When inspecting materials with different sound velocities, it is necessary to consider the impact of sound velocity.
This document, referring to ISO 16828, provides guidance on the application of TOFD technology for the detection, localization, and dimensional measurement of discontinuities in fusion welded joints, as well as the unique functions and limitations of this technology. In manufacturing process inspection and in-service inspection, TOFD can be used as a standalone technology or in combination with other non-destructive testing (NDT) methods or technologies.
This document establishes four inspection levels (A, B, C, and D) in accordance with ISO 17635. The higher the inspection level, the higher the inspection reliability. This document also provides guidance on selecting an inspection level.
This document allows for the evaluation of TOFD indications for subsequent acceptance. This evaluation is based on the assessment of the transmission wave, reflection wave, and diffraction wave signals in the TOFD image.
This document does not include acceptance levels for discontinuities.