Tensile Properties and Resistance to SSC of Sour Service High Strength Steels after Cold End-Sizing and Thermal Stress-Relieving

摘要

The manufacturing of integral connections in OCTG includes cold end-sizing operations that may impact the SSC resistance of the cold-formed ends of high strength sour service pipes. The common process to recover this SSC resistance is thermal stress-relieving, but the latter raises concerns and is subjected to heterogeneous requirements from standards and from end-users. This article discloses how the tensile properties behave after thermal stress-relieving with regards to the cold-forming history of the material (crimping vs. expanding of the outside diameter) and how this behavior correlates to the SSC resistance of pipe-ends sampled after industrial operations of end-sizing followed by induction stress-relieving operation.