OCTG - Model H40, J55, K55 -Casing Coupling

The structure of the tubing coupling: the end of the tubing is connected with the inner wall of the coupling by a tapered thread, and the end of the coupling body and the tubing are connected by a flat thread with the same thread and the same pitch. It has the characteristics of alleviating the stress concentration at the root of the external thread of a single tapered threaded tubing, which is not prone to fatigue fracture and has a good connection effect. Effectively prevent the oil well tubing from breaking off.

The coupling adopts phosphating treatment, which has good wear resistance and corrosion resistance, and strong thread resistance.

Couplings are divided into tubing couplings and casing couplings. Common steel grades are J55, K55, N80, L80, P110, etc.