X70 pipeline steel with hydrogen sulfide corrosion resistance for longitudinal welded pipe and production method of X70 pipeline steel

An X70 pipeline steel with hydrogen sulfide corrosion resistance for a longitudinal welded pipe comprises the following components in percentage by weight: 0.030-0.060% of C, 0.15-0.30% of Si, 0.55-0.95% of Mn, less than or equal to 0.010% of P, less than or equal to 0.0010% of S, 0.10-0.30% of Cr, 0.05-0.15% of Mo, 0.015-0.065% of Nb, 0.02-0.05% of V, 0.01-0.02% of Ti and less than or equal to 0.004% of N. The X70 pipeline steel is produced through the following production steps: smelting, casting all components into a blank, and heating the blank; performing hot rolling; performing laminar cooling; and rolling. The X70 pipeline steel has the advantages as follows: the yield strength Rt0.5 is 500-545 MPa, the tensile strength Rm is 600-660 MPa, the yield-strength ratio (Rt0.5)/Rm is less than or equal to 0.86, the elongation A50mm is larger than or equal to 35%, the impact energy KV2 at 20 DEG C below zero is larger than or equal to 290 J, the DWTT cross section shear rate SA at 15 DEG C below zero is larger than or equal to 95%, and the hardness number HV10 is less than or equal to 225. According to the NACE TM 0284 standard, HIC inspection is carried out in an A solution, the CLR value, the CTR value and the CSR value of a cross section of an X70 pipeline steel sample are