A kind of e36 extra-thick steel plate for polar ocean platform and its manufacturing method

Abstract

The invention discloses an E36 super-thick steel plate for a polar ocean platform and a manufacturing method of the E36 super-thick steel plate. Steel contains 0.08%-0.15% of C, 0.20%-0.50% of Si, 1.05%-1.35% of Mn, smaller than or equal to 0.003% of S, smaller than or equal to 0.010% of P, 0.06%-0.08% of V, 0.015%-0.040% of Als, 0.008%-0.015% of N and 0.15%-0.40% of Ni, and also can contain one or more of smaller than or equal to 0.15% of Cr, smaller than or equal to 0.15% of Cu and smaller than or equal to 0.04% of Ti, and the balance Fe and unavoidable impurities. A production process of the steel plate comprises the steps of die casting, hammer cogging, forging stock rolling, controlled cooling, normalizing and low cooling after discharging. The prepared 250-mm super-thick steel platehas the good obdurability on the full-thickness section and the good Z-direction performance, and meets the strict requirements on the low-temperature tenacity of the steel plate in a polar environment.

Description

technical field [0001] The invention belongs to the field of iron and steel material preparation, in particular to a large-thickness structural steel plate used for offshore platforms, in particular to an E36 extra-thick steel plate for polar ocean platforms and a manufacturing method thereof. Background technique [0002] In recent years, with people's continuous exploration and development of the ocean field, the steel required for the matching ocean engineering and its R & D and production have become the top priority. Since the service time of the ocean platform is 50% longer than that of the ship, its The steel plate used must have the characteristics of high toughness, high strength, fatigue resistance, lamellar tear resistance, and good weldability. The traditional 100-150mm thick steel plates for offshore platforms can no longer meet the market requirements. The thickness specifications of steel for offshore platforms are getting larger and larger, and the market sha...

AI Technical Summary

Problems solved by technology

[0004] CN201510120477.8 discloses S355G10+N steel plates for large-thickness offshore platforms and their production methods. This invention patent proposes a rolling method for S355-grade steel with a maximum thickness of 100-150 mm for marine engineering, which cannot meet the requirements of 200 mm steel for marine engineering. and above the need for larger thickness dimensions

[0005] CN201310203415.4 discloses a steel for offshore platforms with a thickness of 150 mm and its production method. The invention patent proposes a method for producing steel for marine engineering with a maximum finished product thickness of only 150 mm by using continuous casting slabs, and the steel of the invention is only The strength index of 36kg steel plate has been achieved, but the achievable index of low temperature toughness has not been mentioned, which cannot meet the needs of modern marine engineering steel for low temperature resistance and large thickness steel plate

[0006] CN201110135930.X discloses a large-thickness offshore platform steel and its production method. The invention patent uses electroslag remelted billets as raw materials. The maximum thickness of the product is 300mm, but the strength level is only 32kg. Not only the process cost is high, but also Unable to meet the steel index requirements for higher-level offshore platforms

Images