An ultrasonic testing technique has been developed for quality evaluation of Pressurised Heavy Water Reactor (PHWR) fuel element end plug welds. A focused high frequency shear wave is directed to the weld zone from half skip distance to detect lack of fusion, prosities and root cracks in the weld zone. To enhance the speed of inspection two point focused probes are used simultaneously to test both the welds together. Select/reject criteria have been evolved to sort out the defective weld by examining more than 700 PHWR fuel element end plug welds.
展开▼
