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

Abstract

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.

Description

technical field [0001] The invention belongs to the technical field of structural steel for ship hulls and ocean engineering, and particularly relates to a 36kg-grade steel for offshore platforms and a production method thereof. The 5-80mm thick 36KgZ35-grade steel for offshore platforms is produced by a normalizing process. Background technique [0002] In the second half of 2008, there was a global economic crisis, and all walks of life were seriously affected by the economic crisis. The shipbuilding industry, as a supporting industry for economic development, was also affected to a certain extent. Many shipyards turned to the offshore engineering steel market. According to statistics, The strength level of steel used for offshore platforms is mainly 36kg, and its consumption accounts for more than 90% of the total consumption. The maximum consumption of E-grade plates is about 50%. 60mm accounts for about 30%, and the ratio of 60mm or more and 10mm or less is within 10%. ...

AI Technical Summary

Problems solved by technology

The higher the strength level, the greater the demand for water cooling strength. With the increase of water cooling strength, it is easy to produce uneven water cooling on the same board surface due to the limitation of equipment status, capacity and cooling method, resulting in uneven performance; As the thickness of the steel plate increases, the cooling penetration effect gradually weakens, resulting in uneven performance in the thickness direction

Therefore, the process window of the TMCP process is relatively narrow, and it is difficult to produce high-grade steel, especially steel plates with a certain thickness.

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