Offshore platform rack steel with thickness of more than or equal to 114 mm, and production method thereof

Abstract

The invention relates to an offshore platform rack steel with a thickness of more than or equal to 114 mm. The offshore platform rack steel comprises, by weight, 0.14-0.192% of C, 0.15-0.35% of Si, 0.98-1.3% of Mn, less than or equal to 0.014% of P, less than or equal to 0.008% of S, 0.15-0.35% of Cr, 1.2-1.5% of Ni, 0.40-0.58% of Mo, 0.15-0.26% of Cu, 0.032-0.068% of V, less than or equal to 0.0003% of [O], less than or equal to 0.007% of [N], less than or equal to 0.003% of Sn, less than or equal to 0.003% of As, and less than or equal to 0.002% of Sb. The process steps comprise: smelting through an electric furnace, a LF refining furnace treatment, vacuum smelting in a VD furnace, vacuum pumping and pressure maintaining in the VD furnace, soft blowing in the VD furnace, continuous casting, electroslag re-melting smelting, electroslag billet heating, sectional rolling, air cooling, and a heat treatment to be spare, wherein the heat treatment adopts a quenching and tempering treatment manner. According to the present invention, the electric furnace and electroslag re-melting combination manner is adopted to produce the steel, wherein a yield strength of the steel is at least 650 MPa, a thickness of the steel is 114-152 mm, and a cost of the steel prepared by the method of the present invention is lower 500-700 yuan / ton compared to a cost of a forging manner so as to easily enhance product competitiveness.

Description

technical field [0001] The invention relates to an offshore platform steel and a production method thereof, in particular to a rack steel for an offshore platform with a thickness ≥ 114 mm and a yield strength greater than 650 MPa and a production method thereof. Background technique [0002] An offshore platform is a marine engineering structure that provides a place for offshore operations and living for the development and utilization of marine resources. With the rapid development of ocean development, offshore platforms have been widely used, such as the exploration of seabed oil and natural gas. and development, laying of submarine pipelines, utilization of ocean wave energy, construction of offshore airports and offshore factories, etc. At present, the most widely used field of offshore platform is the exploration and development of offshore oil and gas resources. [0003] The offshore drilling platform is the work base for subsea oil and gas exploration and exploita...

AI Technical Summary

Problems solved by technology

[0006] The present invention is to solve the problem that the converter cannot be used to produce thickness greater than 114 mm, although it can be produced by forging, but the cost is high and the efficiency is low. Combining electric furnace and electroslag remelting to produce rack steel for offshore platforms with a yield strength of at least 650 MPa and a thickness greater than 114 mm, and the cost is 500-700 yuan / ton steel lower than that of forging and its production method

Images