Hot-rolled steel plate for 560 MPa-grade deep sea pipeline and production method thereof

The invention provides a hot-rolled steel plate for a 560 MPa-grade deep sea pipeline. The steel plate comprises the following components in percentage by weight: 0.04-0.09% of C, 0.18-0.45% of Si, 1.2-1.75% of Mn, P not more than 0.020%, S not more than 0.003%, Nb not more than 0.08%, Ti not more than 0.025%, V not more than 0.03%, Mo not more than 0.20%, Cu not more than 0.25%, 0.10-0.30% of Ni, Cr not more than 0.25%, N not more than 0.008%, 0.010-0.040% of Al, Al/N not less than 2, and the balance of iron and inevitable impurities. A method comprises the following steps: the heating temperature of a continuous casting blank is 1160-1230 DEG C; the heating time is 1.0-1.5 min/mm; the insulation time of a soaking zone is not shorter than 60 min; the reduction of rough milling pass is not less than15%; the transverse rolling deformation is not less than 30%; the deformation of final pass is not less than 20%; the temperature is 1000-1100 DEG C; the finish rolling temperature is 750-830 DEG C; the accumulated deformation is 60-75%; the after-rolling cooling speed is 15-35 DEG C/s; the final cooling temperature is 400-500 DEG C; and finally, the air cooling is performed. The steel plate is excellent in transverse and longitudinal performances, excellent in corrosion resistance and suitable for serving as a raw material of manufacturing a deep sea oil and gas transportation pipeline.