ULTRASONIC TIME-OF-FLIGHT DIFFRACTION (TOFD) PROCEDURE FOR WELDS ACCORDING TO ASME CODE CASE 2235 IN LIEU OF RADIOGRAPHIC EXAMINATION

摘要

Prior to application of automated ultrasonic examination by TOFD for welds according to ASME Code Case 2235 1997, the following items should be considered :(1) Performance demonstration of TOFD technique for planar type flaws referenced in the acceptance criteria (Max.0 06t reference flaw size t = test block thickness)(2) Scanning method for detection of transverse flaws(3) Shape of embedded flaws in a qualification block.(4) Others (Basic examination conditions/parameters, etc.)Several experiments of UT technique performance demonstrations were conducted in accordance with Code Case 2235 using test blocks with embedded planar type flaws The performance demonstrations confirmed that The Japan Steel Works ( JSW) TOFD procedure fully satisfies Code Case 223 5 .This paper describes JSW TOFD ultrasonic technique performance test results in lieu of radiographic examination using test blocks with embedded artificial planar type flaws sized according to the acceptance criteria of Code Case 223 5.