... : 3.68~16.13mm 3.ISO Standard,API certificate 4.Gread: J55K55N80L80C90P110 API 5CT Casing and Tubing 1. On sale ... seamless API-5CT Casing pipe, Tubing pipe, Coupling, OCTG, Oil ... , Tubing pipe, OCTG, Oil pipe for oilfield: According to API SPEC 5CT.3. Steel grade: J55, K55, L80, N80 ... -1/2" to 20",6. Threads: BTC, LTC, STC.7. Length range: R1, R2, R38. If you interested in ...