Taking different pipeline steels as the research object, the differences of 匡威1970s水蜜桃色官方-免费-完整版片s measured by image analysis method, vernier caliper method and lateral expansion meter method were compared, and the accuracy and stability of determining the 匡威1970s水蜜桃色官方-免费-完整版片by side expansion value were verified. The 匡威1970s水蜜桃色官方-免费-完整版片 of X80 steel solid wire automatic welding girth weld at different temperatures was carried out. The results show that for materials with poor toughness and uneven toughness, as well as samples with distortion after impact fracture, the 匡威1970s水蜜桃色官方-免费-完整版片 should be measured by lateral expansion instrument. For pipeline steel, the accuracy and stability of the results of the 匡威1970s水蜜桃色官方-免费-完整版片determined by the side expansion value were good. The 匡威1970s水蜜桃色官方-免费-完整版片 corresponding to the 匡威1970s水蜜桃色官方-免费-完整版片of X80 steel solid wire automatic welding girth weld was 0. 90 mm.