Small sample test technology for strength of X70 pipeline girth weld

The mechanical properties of X70 pipeline girth weld were tested layer-by-layer by small tensile method. From the test results of small samples, not only the tensile strength of the butt girth weld could be obtained, but also the tensile strength distribution of different regions of the weld could be obtained. The results show that the yield strength of butt girth weld was about 20% lower than that of base metal, and the yield strength of different layers in the weld was also quite different.