管线钢管拉伸试验的研究

Studies on Tensile Test to Steel Linepipe

介绍了近年来采用各种拉伸试样测试管线钢管周向拉伸性能的试验方法。研究发现矩形试样对钢管的拉伸性能有一定程度的低估,圆棒试样的屈服强度值要高于相对应的矩形试样,且接近于环胀试样测得的值,特别是当钢管经过水压试验后,矩形试样和圆棒试样的抗拉强度差异不大。拉伸试验方法及取样时钢管工序的不同,影响到钢管管体横向屈服强度检测结果。

Introduced in the essay are the test methods with a veriety of test specimens for circumferential tensile properties of steel linepipes, which have been used over the recent years. It is identified that with the rectangular specimen, the tensile properties are under-evaluated in certain extent, while the yield strength value as determined with the round bar specimen is greater than that from the correspondent rectangular specimen, and moreover, the result of the test with round bar specimen is rather close to the yield strength value from the test with the ring-expansion specimen. Also identified is that the tensile strength values from tests with the two different specimens are barely differentiated from each other, when the steel tube has undergone inspection processes such as hydrostatic test. The transversal yield strength of the tube as determined by the test is influenced by both the tensile test method as chosen, and the operation process the tube is undertaking, when sampling is conducted thereupon.