Preliminary Study on Residual Sress in High Grade Steel Wire-line Coring Pipe

Abstract:

There is a viewpoint saying that the residual stress in pipe is one of the causes of non-normal damage of wire-line coring drill pipe, based on which, the detection comparison was made on the residual stress in the manufacturing process of cold drawing wire-line coring pipe with different heat treatment and straightening processes by ring cutting method. The residual stress produced in cold drawing pipe manufacturing process is thought to be in existence but is controllable. With appropriate manufacturing measures, the residual stress in high grade alloy pipe can be controlled in an acceptable range, and rare qualified pipes break occur due to the residual stress. The pipe breaking accident should be reduced by paying attention in pipe manufacturing, drill pipe processing and the field application.