SU1699702A1 - Broadened downstairs ingot mold for pouring steel - Google Patents

Abstract

The invention relates to metallurgy and can be used in the casting of steel ingots. The purpose of the invention is to reduce the consumption of materials, labor costs for operation of the ingot molds, and to increase the yield of the metal golle by reducing the size of the head trimmings. The mold consists of a housing 1, a heater, located on the outer surface of the head of the molds, consisting of a casing 2, filled from the inside with heat-insulating refractory material 3. The casing can be detachable and one-piece. The use of such a mold allows one to replace single-use heat insulating inserts placed on the inner surface of the mold, reduce labor costs for the preparation of molds with casting molds for steel casting and save metal by reducing the size of the head trim of ingots. 2 silt, 1 tab. tv, JV.4 (| Г wi W (ЈFig .1

Description

YU

15

The invention relates to metallurgy and can be used in the casting of steel ingots.

The purpose of the invention is to save thermal insulation materials, reduce labor costs during operation of the mold and increase the yield of metal from ingots.

FIG. 1 shows the mold, cut; in fig. 2 shows section A-A in FIG. one .

The mold consists of the housing 1 and the insulation, which is a detachable casing 2 with an internal heat insulation layer 3. Various materials with a low thermal conductivity can be used as the heat insulation layer, for example, kaolin wool, mineral fiber, diatomaceous earth, etc.

The mold is prepared for work as follows.

A heat insulator is mounted on the body of the mold at the head, which is a casing made of sheet steel with a thickness of 3 mm, solid or detachable, provided with covers with a width equal to the thickness of the heat insulating layer at the bottom and top. The top cover is welded after filling the cavity of the insulation with heat insulating material. If the casing is detachable, it is connected by cuffs 4.

Made several options for insulation of various heights - from 0.2 to 0.8 height of the mold. Tests are carried out on molds, wider 20

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For kaolin wool, the optimal thickness of the thermal insulator layer is 90-110 mm. Thermal insulation of the metal of the ingots is carried out immediately after the filling of the molds with perlite at a rate of 2.5 kg / ton. The comparison is carried out with a mold having an internal refractory liner made of kaolin wool MKRP-3 0, 30-AO mm thick and 50 mm high.

With a height of insulation equal to 0.5-0.7 of the height of the mold, the depth of the shrinkage shell is less than that of the well-known mold, and exceeds the analogous figure for molds of other structures. At the same time, the insulation is used repeatedly during the whole campaign of exploitation from a spoon, and in a well-known mold it is used only on one spill. With a height of insulation less than 0.5 mm, the depth of the shrinkage shell increases due to insufficient insulation of the head part of the ingot. At a height of more than 0.7 mm, the height of the mold is not observed to further decrease the shrinkage shell size, which leads to an additional consumption of materials for the manufacture of insulation.

The use of the mold allows to reduce the consumption of heat insulating material for the manufacture of insulation and labor costs to prepare the mold for casting during the whole period of its operation. The consumption of heat insulating material, 1 ton of steel, when using sand liners, is 6–7 kg / ton, and from fiber to bottom, the casing is cast from cast iron of 40–1.5 kg / ton grade MKRP-ZO . With

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wall thickness 175-190 mm.

Example. In the wider downwards mold weighing 16.5 tons and sizes

 2650 mm. wall thickness 1370x1753

170-195 mm, height of insulation equal to 100 mm, thickness of fiber insulation 100 mm, poured steel grades 10 JV and 3 JV. The depth of shrinkage defects vary from 10.3 to 11.6%.

Steel is melted in oxygen converters with a capacity of 350 tons and poured into molds through a gate valve with a 60 mm collector diameter. As a heat insulator, kaolin wool with a thickness of 50 to 150 mm is used, the insulation casing is made of steel sheet 3 mm thick.

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the use of kaolin wool in the amount of 0 kg for the insulation of one mold is about 2 kg per 1 ton of steel. But with 60 fillings in one mold and the use of insulation on 20 compositions, its consumption per ton will be reduced by 1200 times, i.e. equal to 0,0017 kg / t. The cost of manual labor for the preparation of molds with casting molds for casting is reduced by the same amount.

I

The use of a mold results in an increase in the yield of a suitable metal by 0.6-1.6% due to a decrease in the head trim of the ingots due to a decrease in the depth of shrinkage defects compared to the known mold.

five

0

0

five

five

For kaolin wool, the optimal thickness of the thermal insulator layer is 90-110 mm. Thermal insulation of the ingot metal mirror is performed immediately after the mold is filled with perlite at a rate of 2.5 kg / ton. The comparison is carried out with a mold having an internal refractory liner of kaolin wool grade MKRP-3 0, 30-AO mm thick and 50 mm high.

With a height of insulation equal to 0.5-0.7 of the height of the mold, the depth of the shrinkage shell is less than in the known mold, and exceeds the same indicator for the molds of other structures. At the same time, the insulation is used repeatedly during the whole campaign of exploitation from a spoon, and in a well-known mold - on only one tap. With a height of insulation less than 0.5 mm, the depth of the shrinkage shell increases due to insufficient insulation of the head part of the ingot. At a height of more than 0.7 mm, the height of the mold is not observed to further decrease the shrinkage shell size, which leads to an additional consumption of materials for the manufacture of insulation.

The use of the mold allows to reduce the consumption of heat insulating material for the manufacture of insulation and labor costs to prepare the mold for casting during the whole period of its operation. The consumption of mate- rial and heat insulator, 1 ton of steel, when using sand liners, is 6–7 kg / t, and fiber 5

0

the use of kaolin wool in the amount of 0 kg for the insulation of one mold is about 2 kg per ton of steel. But with 60 fillings in one mold and the use of insulation on 20 compositions, its consumption per ton will be reduced by 1200 times, i.e. equal to 0,0017 kg / t. The cost of manual labor for the preparation of molds with casting molds for casting is reduced by the same amount of time.

I

The use of a mold results in an increase in the yield of a suitable metal by 0.6-1.6% due to a decrease in the head trim of the ingots due to a decrease in the depth of shrinkage defects compared to the known mold.

Claims (1)

Invention Formula A downward-wrought casting mold for steel, containing a heater made of heat-insulating material, installed in its head part, so that, in order to save heat-insulating materials, reduce labor costs during its operation and increase the yield of metal, the heater is equipped with metal casing installed on the outer surface of the mold and has a height equal to 0.5-0.7 height of the mold. The results of comparative tests known and proposed molds The mold with the height of insulation, dale from. The height of the mold Depth of shrinkage defects of the mold,%: of the proposed 17.3 T1.6 11.5 11.5 Yu.4 10.3 Yu.Z known 12.0 0.2 0.3 0.4 0.5 0.6 0.7 0.8