Thick-specification X80 pipeline steel plate with process time being shortened and manufacturing method thereof

Abstract

The invention discloses a thick-specification X80 pipeline steel plate with the process time being shortened. The thick-specification X80 pipeline steel plate is characterized in that the steel plate comprises, by mass, 0.02%-0.06% of C, 1.6%-1.9% of Mn, 0.1%-0.35% of Si, 0-0.0006% of S, 0-0.010% of P, 0.055%-0.08% of Nb, 0.008%-0.03% of Ti, 0-0.008% of V, 0-0.06% of Alt, 0-0.010% of N, 0-0.006% of O, 0-0.15% of Mo, 0-0.20% of Cu, 0.2%-0.4% of Ni, 0-0.35% of Cr, 0-0.01% of Ca, the balance Fe and inevitable impurities. The main process of the thick-specification X80 pipeline steel plate comprises the steps of molten steel smelting, continuous casting, plate blank reheating and hot rolling; and the hot rolling process comprises the steps of intermediate blank cooling, water cooling, stack cooling and straightening. According to the thick-specification X80 pipeline steel plate with the process time being shortened and the main processes, an intermediate blank is uniformly cooled through an intermediate blank moderate cooling system and is cooled to the rolling starting temperature of second-stage finish rolling, thus, the process time can be substantially shortened, and the production efficiency is improved.

Description

technical field [0001] The invention relates to a steel plate for X80 pipelines and a manufacturing method thereof, in particular to a steel plate for producing thick X80 steel grade pipelines with shortened process time and a manufacturing method thereof. Background technique [0002] At present, fossil energy still occupies a dominant position in the energy structure in the energy demanded by the world. The rapid growth of the world economy in recent years has greatly driven the rapid growth of fossil energy demand, which has also greatly promoted the development of long-distance transmission pipelines. Transmission efficiency, lower investment, and the development trend of steel for long-distance oil and gas pipelines is to develop towards high-strength or ultra-high steel grades. At present, the highest steel grade of pipeline steel used in countries all over the world is X80 steel grade. In order to improve the delivery pressure, X80 steel grade has been developed in t...

AI Technical Summary

Problems solved by technology

It will cause a large temperature difference between the upper and lower surfaces of the intermediate billet and the core, resulting in difficulties in subsequent rolling, and at the same time cause a large difference in the structure of the upper and lower surfaces of the final steel plate, which will eventually affect the performance of pipeline steel

Images