SU1405946A1 - Method of bottom casting of steel - Google Patents

Abstract

The invention relates to the field of ferrous metallurgy, in particular to methods of siphon casting of steel, and can be used in the preparation of steel ingots under heat insulating mixtures. The purpose of the invention is to improve working conditions by reducing the build-up during the extraction of the ingot after solidification. The method includes pre-placing a heat-insulating mixture on the bottom of the mold, followed by siphoning the liquid. dust emission when stripping an ingot. 1 tab. (L

Description

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The invention relates to ferrous metallurgy, in particular to methods of siphon casting of steel, and can be used in the preparation of steel ingots under heat insulating mixtures.

The goal of the invention is to improve working conditions by reducing the volume of the ingot either when the ingot is removed after hardening.

The method is characterized as follows.

Before the pouring of steel, heat-insulating mixture is introduced into paper bags at the bottom of the mold, then liquid steel is poured with a siphon and immediately after the end of pouring, the entire surface of the heat-insulating mixture is covered with a layer of crushed silicate lump. In this case, the silicate lump softens due to the heat of the ingot and forms a crust, which prevents the splitting during the stripping of the ingot. Example. The proposed method was implemented by casting a batch of round ingots of tubular steel. Steel was cast in round-section molds installed on multisite pallets with widening downwards.

Before pouring metal into the bottom of each mold, a heat-insulating perlitographite mixture was placed in paper bags in the amount of 1, 2 kg (4.5 l). Sizes of ingot: diameter of the larger section - 380 mm, smaller - 370 mm, weight, 7 g

Immediately after the metal was poured, a layer of crushed silicate lump was poured over the perlitographite mixture in the amount of 0.225 l. Spreading from the heat of the ingot, the silicate lump covered the entire surface of the heat insulating layer on the ingot with a dense crust. Two hours after pouring, the crystallized and cooled ingots were removed from the molds and loaded onto the wagons.

When the molds from ingots and their laying on the die-production cars due to the heat-insulating mixture left on the ingot were not observed.

Another batch of steel ingots was cast in a known manner (without the coating of crushed silicate lump).

The results of measurements of the pollution of the atmosphere at workplaces in the open-hearth shop during the casting of steel pipe ingots with the use of pearl

tografitovoy mixture proposed and known methods are given in the table. . ;

Sampling point

The amount of dust, mg / cubic meter, according to the method

Known (prototype)

0 5 0

Jq 5

P

five

five

At the casting site at the time of steel casting 4.0 4.0

On the bottling valve at the time of steel casting 3,, 0 3,0

On the filling crane at the time of stripping ingots and loading them onto platforms 3.0 5.0

The results of a comparative analysis of the quality of the ingots showed that the depth of the burial and shrinkage shell is the same in both cases and is located in the volume of the insulating insert, the rest of the ingots are dense. At the same time, the dust emission during the extraction and laying of the cast ingots obtained by the proposed method is less 1.7 times.

 Thus, the proposed method of siphon-casting steel provides a significant reduction in production during the extraction and transportation of ingots without reducing the heat-insulating properties of the mixture and the quality of the resulting fuels. . .

Claims (1)

Invention Formula The method of siphon casting of steel, including the preliminary placement of a heat-insulating mix at the bottom of the mold; si and subsequent slugging of liquid steel with a siphon into the mold, which differs from the fact that., in order to improve working conditions by reducing pyshevsevlenie when removing the ingot after solidification, the entire surface of the heat insulating mixture immediately after the end of pouring is crushed with a layer of crushed silicate lump.