Tubing coupling is a kind of drilling tool in oil field, which is mainly used for tubing connection. The tubing coupling mainly solves the problem of fatigue fracture of existingcoupling due to stress concentration.
The tubing coupling structure is that the tubing end and the inner wall of the couplingbody are connected by tapered thread, and the end of the coupling body and the tubingare connected by the same thread and the same pitch horizontal thread. The utility mode has the characteristics of alleviating the stress concentration at the root of the outerthread of a single conical thread connecting tubing, and is not easy to produce fatigue fracture, and has good connection effect. Effective prevention of tubing string break-offa ccident.
The coupling adopts phosphating treatment, whichas-good wear resistance,corrosionresistance and thread stickiness resistance.
Couplings are divided into tubing couplings and casing couplings.