50mm K型坡口对接焊缝的PAUT检测方法研究

Research on PAUT Inspection Method for 50mm K-groove Butt Welds

通过制作6块参数为500×800×50的材料的带典型缺陷的K型坡口厚壁碳钢对接焊缝试块进行研究,使用PAUT检测技术和TOFD检测技术对试块可能存在的缺陷进行检测试验和工艺研究,验证PAUT&TOFD检测技术对厚壁碳钢对接焊缝的检测方法;且通过制作带缺陷的K型坡口试块模拟单边受限的特殊检测情况,即只能在焊缝单侧进行检测的特殊情况下,PAUT检测能力验证并与RT检测结果进行比对;最后通过对试块缺陷进行切片,验证缺陷的实际尺寸和类型。通过以上大量的试验工作得到试验结论证明对焊缝进行双侧PAUT&TOFD检测能够得到最好的检测效果,几乎所有的焊缝埋设缺陷都被找出,单侧检测通过检测工艺研究能找出焊缝埋设的部分缺陷。同时,应用一发一收方式进行检测试验探索,结果也能发现部分缺陷,但是有一定的检测局限性。

By making 6 pieces of 500×800×50mm butt weld K-groove thick-walled carbon steel test block with typical defects, test experiment and process study is taken for the pertential defects in the test piece using PAUT and TOFD method, to verify inspection method using PAUT TOFD technology for thick-walled carbon steel butt weld. Special testing situation as unilateral inspection limitation is simulated by making the defective K-groove test blocks, which means the joint could only be inspected unilaterally. Inspection ability of PAUT is verified and contrasted with RT inspection results, and finally with the test block defects slicing to verify the actual size and type of the defects. Inspection test conclusions is obtained by the above experimental work that the bilateral weld inspection with PAUT TOFD could get the best inspection results, almost all of the welds defects buried can be find out, inspection by unilateral weld inspection technology can find most of the defects in welds. Meanwhile, explore the application of pith-catch technical method, also can find a part of defects, but there are certain inspection limitations.