Clean steel smelting method of anti-S steel oil well pipe

Abstract

The invention provides a clean steel smelting method of an anti-S steel oil well pipe, which relates to a smelting and preparing technology of an oil well pipe blank used in a corrosive oil-gas fieldenvironment. Clean steel comprises suitable chemical compositions by weight percent: 0.20-0.35 percent of C, not more than 1.00 percent of Si, not more than 0.60 percent of Mn, not more than 0.015 percent of P, not more than 0.010 percent of S, not more than 1.50 percent of Cr, 0.15-1.0 percent of Mo, 0.01-0.06 percent of Als, not more than 0.09 percent of Ti, not more than 0.05 percent of Nb, notmore than 0.0030 percent of N, not more than 0.0030 percent of O, not more than 0.0002 percent of H and Fe and the balance of unavoidable impurities. The clean steel smelting method adopts the following production technical lines by aiming at the clean steel with the compositions: choosing matching materials; smelting in an arc furnace; refining in an LF furnace; refining in a VD furnace; continuously casting in an arc shape; controlling hydraulic pressure and casting in full protection. The clean steel smelting method reduces the impurity content in the steel by controlling the proper content of C, Mn, P, S, Cr, Mo, N, O, H, and the like, the impurities are smaller and dispersive by the control of a subsequent technology, the component distribution is more uniform, tissues are evenly thinned, and the combination property of the anti-sulfur oil well pipe is ensured.

Description

technical field [0001] The invention relates to an advanced steel smelting technology, in particular to a pure steel smelting method for an anti-S steel oil well pipe. Background technique [0002] The purity of steel is usually evaluated by the content of harmful elements in steel, including P, S, N, H, O (for ultra-low carbon steel C is also used as a harmful element), and the number, shape and size of non-metallic inclusions. When the content of these elements is high, various properties of steel will be reduced, such as tensile strength, toughness, formability, weldability, crack resistance and corrosion resistance, fatigue performance, etc. At the same time, it will also reduce the surface quality of the steel. [0003] With the rapid development of all walks of life, higher requirements are placed on the performance of steel. For example: car panels require C, N, and T.O to be less than 0.0020%, while beverage cans not only require T.O to be less than 0.0020%, but al...

AI Technical Summary

Problems solved by technology

At the same time, it will also reduce the surface quality of the steel

Images