Production process for controlling large inclusions in acid-resistant pipeline steel

Abstract

The invention discloses a production process for controlling large inclusions in acid-resistant pipeline steel. Through systematic analysis on a pipeline steel inclusion control mechanism adopting a BOF-RH-LF production process, the component design is reasonably performed; the pipeline steel comprises the following components in percentage by weight: 0.02-0.04 percent of C, 0.10-0.30 percent of Si, 1.00-1.30 percent of Mn, less than or equal to 0.013 percent of P, less than or equal to 0.0010 percent of S, 0.030-0.070 percent of Nb, 0.006-0.020 percent of Ti, 0.10-0.30 percent of Ni, 0.10-0.30 percent of Cr, 0.10-0.30 percent of Cu, 0.015-0.050 percent of Al and the balance of Fe. The production process disclosed by the invention has the benefits that the content of sulfurs in molten steel before calcium treatment is ensured to be less than 10 ppm; the quantitative calcium treatment is performed after the end of LF; the purpose of improving the purity of the molten steel is achieved, so that the internal quality of steels is improved, and the economic benefits are improved.

Description

Technical field [0001] The invention belongs to the field of metallurgy and relates to a production process for controlling large inclusions in acid-resistant pipeline steel. Background technique [0002] With the continuous increase of energy demand in the world economy, the dependence on pipeline transportation of oil and natural gas is increasing, and the service environment of pipeline transportation pipelines is becoming more and more demanding. For the transportation of sour oil and gas, the base material needs to have acid and corrosion resistance. , In order to meet the acid resistance, the composition design needs to adopt extremely low carbon and extremely low sulfur. Desulfurization leads to a large number of aluminum inclusions in the steel, which leads to unqualified flaw detection and inclusion inspection, and seriously affects the performance of the steel plate. . [0003] Acid corrosion-resistant pipeline steel is mainly used to make pipelines for transporting sour...

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Problems solved by technology

[0002] With the increasing demand for energy in the world economy, the dependence on pipeline transportation of oil and natural gas is increasing, and the service environment requirements of pipeline transportation pipelines are becoming more and more stringent. For the transportation of acidic oil and natural gas, the base material must have acid and corrosion resistance. , in order to meet the acid resistance, extremely low carbon and extremely low sulfur should be used in the composition design. Desulfurization leads to the production of a large number of aluminum-based inclusions in the steel, which leads to the failure of flaw detection and inclusion inspection, and seriously affects the performance of the steel plate.

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