API 5CT 9-5/8 N80 Stc casing coupling

Application: casing coupling is a kind of drilling tool in oil field, which is mainly used for casing connection. The casing coupling mainly solves the problem that the existing coupling is prone to fatigue fracture due to stress concentration.

Structure:The casing end is connected with the inner wall of the coupling by tapered thread, and the end of the coupling body is connected with the oil pipe by the same thread and the same pitch flat thread. The utility model has the characteristics of relieving the stress concentration at the root of the external thread of the single taper thread connecting sleeve, not easy to produce fatigue fracture, and the connection effect is good.

The thread type of casing couplngs main include: Long Round-thread Casing Coupling(LC), Short Round-thread Casing coupling(SC), Buttress Thread Casing Coupling(BC), and steel grade mainly include: J55, K55, N80, L80, P110 and so on.