Piercing Failure Analysis of Oil Casing Pipe

Macroscopic and microscopic morphology observation, physical and chemical properties of pipe material test, hydraulic blasting test, casing type analysis and strength rechecking of casing string were performed for a piercing casing pipe. The failure reasons were analyzed by combining relative theory with tests. The results show that the dint on the outer surface of piercing casing was a fold defect which was the primary reason for the piercing failure of casing pipe. And the pipe body cracking was local overload cracking.