k55 oil tubing 1.J55,K55,N80,L80,P110 steel grade 2.OD:60. ... .70C,N,L,P7.82EU9.45L,C8.64EU88.90(3 1/2")9.20H,J,C,N,L,P6.45NU9.30H ... ,L5.74NU11.00H,J,C,N,L6.65EU114.30(4 1/2")12.60H,J,L,N,C,T12.75NU12.75H ... standards. API 5CT spec j55,k55,n80,l80 seamless oil tubing for oil field service