Hot-rolled steel plate for ocean riser with low cost and high performance and production method thereof

Abstract

The invention discloses a hot-rolled steel plate for an ocean riser with low cost and high performance and a production method thereof. The chemical components of the steel plate comprise C 0.04-0.10%, Si 0.10-0.35%, Mn 1.55-1.85%, Nb 0.02-0.08%, Ti 0.008-0.020%, Al 0.010-0.040%, P less than or equal to 0.020%, S less than or equal to 0.003%, Mo less than 0.20%, Cu less than or equal to 0.25%, Ni less than or equal to 0.30%, Cr less than or equal to 0.25%, N less than or equal to 0.008%, and the balance being Fe and unavoidable impurities, wherein Al / N is greater than or equal to 3, Ni+Cu+Mo+Cr is less than or equal to 0.70%, Nb+Ti is less than or equal to 0.09%, and Ti / N is equal to 2.5-5. CEIIW is 0.40-0.45%, CEPCM is 0.16-0.21%, casting blank heating temperature is 1,160-1,230 DEG C, four-stage heating is adopted, rough rolling temperature is 980-1,120 DEG C, fine rolling temperature is 790-900 DEG C, cooling temperature after rolling is 750-800 DEG C, cooling speed is 5-35 DEG C / s, and final cooling temperature is 430-520 DEG C. The steel plate of the invention has yield strength above 555 MPa, endwise tensile strength above 630 MPa, good cracking resistance, corrosion resistance and fatigue resistance, good comprehensive property, and low cost.

Description

technical field [0001] The invention belongs to the technical field of low-carbon micro-alloy steel, and in particular relates to a low-cost, high-strength, high-toughness hot-rolled steel plate for thick specification marine drilling risers and a production method thereof. Background technique [0002] There are rich oil and gas resources in the marine strata. Today, with the sharp increase in energy consumption, the exploitation and utilization of submarine oil and gas resources are getting more and more attention; it is estimated that 90% of the submarine oil and gas resources are located in the seabed strata with a water depth of more than 1000m, or even 2000m Among them, mining is extremely difficult. At the same time, as the water depth increases, the stress and working conditions of the pipeline become more and more severe, and the performance requirements for the steel used for the pipeline are also more stringent. The riser is an important connection part from the ...

AI Technical Summary

Problems solved by technology

[0006] The thickness of the steel plate used in the present invention is 25-33 mm, and the increase of the thickness of the steel plate will lead to a decrease in the amount of compression deformation from the blank to the steel plate, a decrease in cooling uniformity, and easy occurrence of central segregation, etc., which puts forward higher requirements for the design and production process of the steel plate Require

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