Steel for 36kg-grade ocean platform and production method thereof

The invention relates to steel for a 36kg-grade ocean platform and a production method thereof, belonging to the technical field of a ship body and structural steel for oceanographic engineering. A steel plate with thickness of 5-50mm comprises the following chemical components: 0.14-0.18 percent of C, 0.20-0.50 percent of Si, 1.30-1.60 percent of Mn, 0.02-0.05 percent of Nb, less than or equal to 0.005 percent of S, less than or equal to 0.015 percent of P, 0.020-0.04 percent of Als, and the balance of Fe and inevitable impurities; a steel plate with the thickness of 50-80mm comprises the following chemical components: 0.12-0.18 percent of C, 0.20-0.50 percent of Si, 1.30-1.60 percent of Mn, 0.02-0.05 percent of Nb, 0.02-0.06 percent of V, 0.010-0.020 percent of Ti, 0.10-0.40 percent of Ni, less than or equal to 0.005 percent of S, less than or equal to 0.015 percent of P, 0.020-0.04 percent of Als, and the balance of Fe and inevitable impurities; and in addition, the sum of Nb, V and Ti is less than or equal to 0.12 percent. The production method has the advantages of low production cost, uniform and stable comprehensive performance and good cold bending property.