The Researches about Strength of Gas Production Casing Threads Connection

Hua Tong, Xiao-Hong Tang

Abstract: At present, the commonly used API at oilfield round thread of casing, is prone to damage. The forms of damage include dislocation, perforation, deformation and stress corrosion, nipple leaks, tripping failure and so on. Wherein, the leakage of nipple and tripping failures in deep and ultra-deep wells are especially. This paper regarded abroad oilfield casing leaks literature as the theoretical, based on API casing, analyzed the gas wellbore data in detail, analyzed the strength of the connection of its production casing, and got the finite element analysis stress curves of shale gas well production casing under different conditions, to provides a theoretical reference for the gas well casing joint strength evaluation.

Keywords: gas well, API casing thread, Von Mises equivalent stress, the connection strength, security