... -30mm 3.Grade:J55,K55,L80,N80,P110 etc. 4.Thread:LTC,STC,BTC · API 5CT N80 oil casing pipe 1 ... ,L80,P110,C75,C95 etc.3. Standard:API 5CT & 5B4. thread type:STC,BTC,LTC5. brand name:TPCO6. Min order:20 ... according to the customers' requirement12.Size and surface inspection*Non-destructive test *Thread inspection*Hydrostatic test *Drifting test*Physical and chemical analysis*Hardness ...