Name:tubing couplings Std Ref:API 5CT Grade:J55,K55,N80,L80,C90,P110 ... of Tubing and Casing coupling according to API SPEC 5CT AND 5BAPI couplings for oil tubing and casingSize and ... company manufacture and sell casing and tubing couplings,pup joints, tool joints, adapter pup-joints, adapter ... couplings, stabilizers, air-liquid separators, anchors of oil ...