API-5CT casing steel grades are J55, K55, N80-1, N80Q, P110 …
The API-5CT casing steels commonly used in oil fields are J55, K55, N80-1, N80Q and P110. Casing is mainly used in oil well drilling. According to API-5CT, pipes can be classified as STC (short thread), LTC (long thread), and BTC (support thread) and their joints. The field casing is placed in the wellbore and held in place to prevent ...