With material of high-quality Proved by used for many years and the scientific experiments ,the tubing casing model J55, K55,N80, L80 and P110 our company saled were made of after a multi-channel precision machining processes, together with strict quality control procedures.

Standard:  API  5CT , API 5B

1) Sizes: OD 4 1/2"~13 3/8"(114.3~339.7mm)

2) Grade: J55, K55, N80, L80, P110

3) Standard:  API  5CT, API  5B