Failure analysis of low-carbon steel pipe clamp of pressure pipe

Abstract

Abstract A real case of breakage of several pipe clamps used in the pressure pipe hanger is investigated. In order to examine the cause of failure, various techniques, including element analysis, mechanical testing, optical and scanning electron microscopy, component analysis, and impact testing were used. It was found that the fractures of the pipe clamps occurred at the transition zone between a straight and arc segments, the finite element analysis has shown that the transition had the highest stress concentration. The surface deformation during pipe clamp manufacturing process caused hardness rising and toughness descending, resulting in surface cracks, Under the combined effect of lower ambient temperature and service stress, the surface cracks expanded rapidly and the pipe clamps fractured finally. Improvements in the molding process and the use of appropriate quality control measures can eliminate this problem.