A production method for improving the surface quality of low-grade pipeline steel

Abstract

The invention discloses a production method of improving the surface quality of low-steel-grade pipeline steel. The low-steel-grade pipeline steel is prepared from the following chemical components inpercentage by mass: 0.040-0.080 percent of C, 0.10-0.30 percent of Si, 1.20-1.60 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.0030 percent of S, less than or equalto 0.20 percent of Ni, less than or equal to 0.070 percent of Nb, less than or equal to 0.30 percent of Cr, less than or equal to 0.15 percent of Mo, 0.005-0.02 percent of Ti, less than or equal to 0. 0050 percent of N, 0.001-0.003 percent of Ca, 0.010-0.050 percent of Al and the balance of Fe and inevitable impurities. In the production method, the surface quality of a casting blank is improvedthrough optimization of a smelting process, and the integrity of an iron oxide skin on the surface of a steel plate is improved by adjusting a rolling forming technology, so that a pipeline steel plate with high-quality corrosion resistant surface is obtained, and the quality of a product is improved.

Description

technical field [0001] The invention relates to the technical field of iron and steel smelting, in particular to a production method for improving the surface quality of low-grade pipeline steel. Background technique [0002] As the world's demand for energy increases, oil pipeline transportation is increasingly sought after by countries all over the world. The steel plates demanded in foreign markets are mainly transported by cruise ships, and the transportation cycle is generally 1 to 2 months. The ocean environment is harsh, and steel plates are often subjected to Rainwater or even seawater erosion, the surface quality of the steel plate will deteriorate after arriving at the station, and some may affect the use. At present, pipeline steel adopts TMCP rolling process. In order to improve product performance, low-temperature rolling technology is widely used. The large amount of rolling deformation leads to large deformation of the steel plate surface, and the oxide scale ...

AI Technical Summary

Problems solved by technology

[0002] With the increasing demand for energy in the world, oil pipeline transportation is more and more sought after by countries all over the world. The steel plates demanded in foreign markets are mainly transported by cruise ships, and the transportation cycle is generally 1 to 2 months. The ocean environment is harsh, and steel plates are often damaged. Rainwater or even seawater erosion, the surface quality of the steel plate will deteriorate after arriving at the station, and some may affect the use

At present, pipeline steel adopts TMCP rolling process. In order to improve product performance, low-temperature rolling technology is widely used. The large amount of rolling deformation leads to large surface deformation of the steel plate, and the oxide scale is often damaged on the steel plate. The structure changes during the cooling process. Fast, uneven internal stress, resulting in uneven stress on the surface of the steel plate, the oxide scale obtained on the surface of the steel plate after warm straightening is incomplete, and the place where the oxide scale falls off is prone to rust sources, resulting in deterioration of the surface quality of the steel plate

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