Method for improving mechanical dephosphorization of iron scale of low-carbon cold heading steel wire rod

Abstract

A method for improving the mechanical dephosphorization of iron scale of a low-carbon cold heading steel wire rod belongs to the technical field of steel rolling. Processing steps and control technical parameters are as follows: finish rolling inlet temperature is controlled to be 920 DEG C-950 DEG C, and the finish rolling temperature rising range is controlled to be 80 DEG C-100 DEG C; the spinning temperature is controlled to be 880 DEG C-920 DEG C; the opening times and a heat holding cover of an air cooling line and the opening degree of a fan are regulated, the cooling rate of the phase front section of a spun steel wire rod is controlled to be 2-3 DEG C / s; the temperature of the spun steel wire rod is controlled to be 760 DEG C-740 DEG C when the spun steel wire rod enters the heat holding cover, and the heat holding cover is uncovered at the temperature being 620 DEG C-600 DEG C; and the temperature of the spun steel wire rod is controlled to be 580 DEG C-600 DEG C when the spun steel wire rod is discharged from the heat holding cover, the fan is additionally arranged when the spun steel wire rod is discharged from the heat holding cover, the cooling rate of the spun steel wire rod passing through a temperature zone being 5000 DEG C-400 DEG C rapidly is controlled to be 3-5 DEG C / s, and the passing time is controlled to be 15-25s. The method has the advantages that the phase structure conversion phenomenon in an FeO layer in the iron scale on surface of a hot rolling steel wire rod is reduced obviously, the mechanical dephosphorization is improved obviously, and the wire breaking rate and the loss of a die in the user pulling process are reduced.

Description

technical field [0001] The invention belongs to the technical field of steel rolling, and in particular provides a method for improving the mechanical dephosphorization of oxide scales of low-carbon cold-heading steel wire rods; it is applied to high-speed wire factories to produce cold-drawn low-carbon cold-heading steel hot-rolled wire rods. A technology for controlling iron scale on the surface of hot-rolled wire rods. Background technique [0002] Cold-drawn low-carbon cold-heading steel hot-rolled wire rod, before cold-drawing, it needs to go through mechanical peeling to remove the surface oxide scale. Because the iron oxide scale is hard and brittle, if the phosphorus removal is not clean, the surface of the steel wire will be damaged during drawing, and the wire will be broken in subsequent processing. And it will aggravate the wear of the die, thereby affecting the life of the wire drawing die, so the iron oxide scale on the surface of the wire rod should be easy t...

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Problems solved by technology

In the article "Research on the Isothermal Transformation Behavior of FeO Layer on the Surface of Low Carbon Steel under Air Conditions", the Journal of Iron and Steel Research analyzed the isothermal transformation behavior of the iron oxide surface structure of low carbon steel plates, but did not analyze the phase structure transformation in the continuous cooling transformation process under air conditions. , but there has never been an explanation of the cooling speed control points of the air-cooled line, which lacks on-site practical operability

There has not been any report on the continuous cooling transformation control of iron oxide surface structure of low carbon cold heading steel wire rod

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