The invention relates to manufacturing of a pipeline steel hot-rolled coiled plate for a longitudinal welded
pipe, in particular to 450MPa-grade
carbon dioxide corrosion resistant steel and a manufacturing method of the 450MPa-grade
carbon dioxide corrosion resistant steel. The steel comprises the following chemical components: C, Si, Mn, less than or equal to 0.020% of P, less than or equal to 0.002% of S, less than or equal to 0.008% of Cr, Cu, V, Ti, Al, less than or equal to 0.008% of N and the balance of Fe and inevitable elements. According to the steel plate, the transverse yield strength is 470 MPa or above, the tensile strength is 580 MPa or above, the
yield ratio is smaller than or equal to 0.87, the elongation A50 mm is larger than or equal to 39%, the
impact energy at the temperature of-40 DEG C is 280 J or above, the
drop weight at the temperature of-20 DEG C is larger than or equal to 95%, and according to the ASTM-G111
corrosion standard, the average corrosion rate in the
carbon dioxide environment is smaller than 0.10 mm / a; the longitudinal yield strength is 460 MPa or above, the tensile strength is 570 MPa or above, the
yield ratio is smaller than or equal to 0.86, and the elongation A50 mm is larger than or equal to 38%.