Thick X65 pipeline steel and production method thereof

Abstract

The invention relates to a hot continuous rolling steel belt and a production method thereof, in particular to thick X65 pipeline steel and a production method thereof. The thick X65 pipeline steel is low in cost and can maintain good strength, toughness and drop weight tear performance. According to the technical scheme, the chemical components of the thick X65 pipeline steel comprise, in percentage by weight, 0.07%-0.10% of C, 0.10%-0.30% of Si, 1.40%-1.60% of Mn, 0.020% or less of P, 0.010% or less of S, 0.030%-0.039% of Nb, 0.06%-0.08% of V, 0.008%-0.019% of Ti, 0.15%-0.30% of Cr and the balance Fe and unavoidable impurities. According to the thick X65 pipeline steel and the production method thereof, addition of expensive Mo, Ni and other elements is not needed, the finish rolling inlet temperature of the thick X65 pipeline steel does not need to be lowered substantially, the cost is relatively low, the rolling technology is simple, and operability is high. In addition, the yield strength of the 12mm-17mm thick X65 pipeline steel is 480-518 MPa, the tensile strength of the 12mm-17mm thick X65 pipeline steel is 560-660 MPa, the impact energy at 20 DEG C below zero is 190 J or more, and the drop weight tear area at 20 DEG C below zero is larger than 94%.

Description

technical field [0001] The invention relates to a hot continuous rolling steel strip and a production method thereof, in particular to a thick gauge X65 pipeline steel and a production method thereof. Background technique [0002] Among the five transportation methods of railway, highway, aviation, water transportation and pipeline, pipeline transportation is an economical, safe and uninterrupted transportation method. Pipeline transportation of oil and gas has the characteristics of high efficiency, economy, safety and no pollution. most efficient tool. With the rapid development of pipeline engineering, the rapid development of pipeline steel production has been driven. [0003] Oil and natural gas transmission pipelines are divided into two parts: long-distance pipelines and gathering pipelines inside oil fields. In order to improve the transmission efficiency of the long-distance pipeline, the transmission pressure of the main line is relatively high, and it is require...

AI Technical Summary

Problems solved by technology

By greatly reducing its P and S content, while its Nb content is high, and adding expensive Mo, Cu, Ni and other elements to ensure its drop hammer performance, its production cost is high

[0008] Patent CN103388110A discloses a method for improving the drop hammer performance of thicker specification X60 pipeline steel, the chemical composition is controlled C≤0.12, Si≤0.40, Mn≤1.60, P≤0.025 and S≤0.015, and the following conditions are met: ( 1) Nb, V, Ti or combinations thereof are also added, and the sum of Nb, V and Ti contents is ≤0.15%; (2) Cr, Mo, Ni and Cu or combinations thereof are also added, ( 3) The value of ∑Mn must be between 1.80 and 2.05. The chemical composition of this invention includes Cr, Mo, Ni and Cu or their combination, and its production cost is high

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