47kg grade steel plate used on ocean engineering platform and production method thereof

Abstract

The invention provides a 47kg grade steel plate used on an ocean engineering platform and a production method thereof. According to the invention, low carbon content design is adopted, the alloying elements of Mn, Cr, Ni, Mo, V and Cu are added for micro alloy element intensification, the rolling technique of controlled rolling and controlled cooling is adopted, and finally a lath-shaped bainite and ferritic structure is obtained. Tests show that the steel plate provided by the invention has the yield strength of 480MPa, totally reaching the requirement of a 47kg grade, the tensile strength of the steel plate is 630MPa, and the elongation is 27.5%; the impacting energy of the steel plate is 284J under 40 DEG C below zero and is 290J under 60 DEG C below zero; and the low-temperature toughness of the steel plate is guaranteed. The 47kg grade steel plate can satisfy the requirement of operation of the ocean platform under low-temperature aquatic environment and thereby solves the problem of lower strength of steel used in ocean engineering.

Description

technical field [0001] The invention belongs to the field of ferrous metal materials, and in particular relates to a 47kg grade structural steel plate used for ocean engineering platforms and a production method thereof. Background technique [0002] At present, the yield strength of domestically produced ship plates is generally low, such as the "Hull Structural Steel GB / T 712-2000" standard adopted by most manufacturers. In this standard, the maximum strength and quality level of steel plates are: FH40. So far, the top product of ship plates that our country can produce by itself is EH36, that is, the highest strength level is 36kg yield level, and the lowest temperature that can meet the toughness requirements is -40°C. High-strength ship plates are still short of 40 kg grade steel, let alone 47 kg grade steel for offshore engineering platforms. Moreover, each strength level did not meet the low-temperature impact requirement of -60°C. [0003] From the perspective of s...

AI Technical Summary

Problems solved by technology

From the quality point of view, the carbon equivalent of my country's offshore engineering platform steel products is relatively high, resulting in poor application performance such as weldability, so that users have to take technical measures such as preheating and postheating during welding processing, which not only reduces efficiency, but also deteriorates working conditions, which in turn increases production costs