Cause Analysis of Collapse and Tripping of HP2-13Cr110 Tubing in Well KeS2-2-12

Abstract

The accident of the collapsed and tripped tubing in a high temperature and high pressure gas well during the oil recovery process was investigated. The macroscopic morphology of the collapsed tubing was analyzed, the physical and chemical properties of the collapsed tubing were tested, the collapsed tubing was detected by the magnetic particle flaw detection, and the physical collapse experiment of the used tubing were simulated with the same batch of new tubing. The results show that the physical and chemical properties of the material of the collapsed tubing meet the requirements of the factory standard and API 5CT standard. The main reason for the collapse and failure is that the sand from the formation causes the tubing passage to be blocked, causes the pressure difference between the inside and the outside of the tubing to exceed the collapsing strength of the tubing, results in collapsing and tripping the tubing. In addition, the SCC crack on the outer wall and the corrosion of the inner wall of the tubing have a non-negligible effect on the collapsing and tripping of the tubing.