SU1502170A1 - Apparatus for making three-layer ingot - Google Patents

Abstract

The invention relates to metallurgy, in particular, to the preparation of three-layer ingots. The purpose of the invention is to improve the quality of the ingot. The device contains a mold, a central insert 3, made of the material of the base layer of the ingot, and partitions 4 and 5 adjacent to it on both sides. 3 with a gap between it and the central insert, which is 1-2 times the thickness of the partition, which is 2-5% of the distance between the central insert 3 and the wall 1 of the mold. In this case, the central insertion 3 is made in the head part with the width B, calculated by the formula B = A [1 + _U (T ₁ -T ₀ )] ^. [1 + Α _adt (T ₁ -T _0)] ^-1, where A-width of the mold cavity in the head part, mm

α _U - linear thermal expansion coefficient of the mold material, K ^-1

α _adt coefficient of thermal expansion of the center gusset material K ^-1

T _{0 is the} temperature under normal conditions (293K)

T ₁ is the melting point of the most refractory material of the partitions, K, and the faces of the central insert facing the walls of the mold are made with a slope equal to the slope of the walls of the mold. 2 Il.

Description

This invention relates to metallurgy, in particular to the preparation of three-layer ingots.

The purpose of the invention is to improve the quality of the ingot.

FIG. 1 shows a device, a longitudinal section; in fig. 2 shows section A-A in FIG. one.

A device for producing a three-layer ingot contains a mold 1 with a profitable extension 2, a central insert 3 made of the material of the base layer of the ingot and a partition wall 4 and 5, each of which is made of the material of the peripheral layer of the ingot clad in the ingot corresponding face of the insert 3.

The partitions 4 and 5 are installed with a gap between them and the insert 3, equal to 1 - 2 thicknesses d of the partition 5 or 4, which is 2-5% of the distance / between the central insert 3 and the wall of the mold 1.

The central insert 3 in its head part is made by the width b, calculated by the formula

/, LL + 4L j-iJj) J

l + ttBct T i-rn)

lAcu mold width 1 in its head

parts, mm;

“(Coefficient of linear tem | lovogo rasiireeni mold material 1 (/ ();

.aiT is the coefficient of linear thermal expansion of the material of the central insert 3 (/ ();

T (- temperature under normal conditions is 293 K;

71 is the melting point of most; 1e of the refractory material of the partitions 4 or 5 (K).

Facing the walls of the mold 1, the wounds of the central insert 3 are made with a slope at an angle (5, equal to the slope of the walls of the mold 1.

The device works as follows. The liquid metal of the peripheral layers of the ingot is poured into the corresponding cavity between the wall of the mold 1 and the partitions 4 and 5 by any known method.

At the same time, the liquid meta / ia mirror rises faster than the partitions 4 and 5 melt and does not contact with the surface of the central plate, ensuring both the cleanliness of the metal slurry and the firm and tight connection of its layers, i.e. high quality ingot . The pop-up and accumulating paves of the surface of the metal mirror are non-metal particles that do not come into contact with the central insert 3, as the mold 1 fills, the output 2 is profitable. At the same time, the design of the dimensions of the component parts of the installation provides them synchronous thermal expansion, wall protection

0

five

0

five

0

five

0

five

0

five

molds 1 from destruction and reduction of ingot defects on its narrow faces.

The use of the proposed technical solution allows to obtain three-layer ingots of higher quality due to the exclusion of the possibility of metal contamination with non-metallic inclusions and the formation of a loosened cavity at the boundary of fusion of the layers of the three-layer ingot.

When the mold is filled with liquid metal, the rate at which the metal mirror rises is ahead of the fusion rate of the partitions, which is determined by the size of the partition thickness equal to 2-5% of the distance between the central insert and the wall of the mold. In this case, since the partitions completely cover the plated faces of the central plate, these faces are moistened with liquid metal, free from non-metallic inclusions, which float on the surface of the metal mirror and are brought to profit.

If the partition thickness is less than 2% of the distance, it melts faster than the liquid metal mirrors, and the surface of the central insert can directly contact the metal mirror, on which non-metallic particles are concentrated, and hence the metal ingot is contaminated.

When the partition thickness is greater than 5% of the distance between the central insert and the wall of the mold, the partition does not melt and the penetration of liquid metal is difficult in the gap between the partition and the central insert, which leads to the formation of porosity in the ingot and loose.

The implementation of each partition from the material of the peripheral layer of the ingot, plating this facet of the slab in Litke, excludes the melting of components that are not part of the three-layer ingot, which also leads to an improvement in its quality.

The installation of each partition over the entire () insert with a gap between the drink and the central seat, so-called Icic I 2 is then trapped), it provides the case for cutting off the liquid, liquid with floating slag particles and other letters - tal. Shchsskih VC. | yucheyy from 11.1kakiruyemyh surfaces, which improves the quality of tiles.

With sun; | gap gap, smaller thickness noregorodkp, intense heat exchange between () b () r the liquid metal partitioned by the partition and the massive central insert leads to freezing metal; 1a plated-nuTi) si partition. The partition does not expand, which prevents the liquid metal from contacting the central insert. EU uLU))) exceeds the doubled to1 per1M () rodkp, then the contamination of zo) / fecal / metal metal occurs,: 1a and the gap nj.iaKO-EibiMH and e |) ugimp neme1a.1. First of all, 410 reduces the quality of the ingot.

Performing the central insert in the head part with a width related to the mold size, linear expansion coefficients and the melting temperature of the parts of the device, as well as to the slope of the central insert faces facing the mold walls, equal to the slope of the mold walls, provides simultaneous thermal expansion of the central insert and walls molds, due to which the pressure of expansion / degradation is reduced to a minimum when heated in the process of pouring the central insert onto the walls of the mold, and therefore with Second side - is eliminated strip microporosity and improved quality of the ingot, and on the other - the term increases mold life.

Example. A device for producing a three-layer ingot consisting of steel 12X18H10T, st. 20, 10XSND, the central part of which is Art. 20, contains a mold I type LP-7 of cast iron with a profitable extension 2 600 mm in height, the center insert 3 of art. 20 and adjacent partitions 4 and 5. Partition 4 is made of steel 1 2Х18Н10Т, partition 5 - of steel 10ХСНД. Both partitions are the same size 1120x1580 mm. The thickness d of the partitions 4 and 5 is 5 mm, i.e. 2.3% of the distance / between the center insert 3 and the wall 1 of the mold.

The gap c between the slab and the partitions 4 and 5 is 7 mm, which is 1.4 times the thickness d of the partitions 4 and 5. The dimensions of the central insert 3 are 120 / 100x1580 mm. The width L in its head part is 1118 mm and is calculated by the formula

i,., - M

l + a.a T i-T o) 1120X1 I-f 1.0-1.0 (1783-293) 1

.KG (1783 293)

mm,

10XSND, which is more refractory than steel 12X18H10T.

Facing the walls of the mold 1 facets of the central insert 3 and the walls of the mold 1 are made with the same slope at an angle p equal to 0.5 °.

The metal was poured into the mold using the siphon method.

The ingot obtained in the device is characterized by minimal metal contamination by nonmetallic inclusions, strong and dense fusion of layers.

The walls of the mold after use of the device are undamaged, which allows to increase the service life of the mold approximately 10%.

20

Claims (2)

1. A device for producing a three-layer ingot containing a mold, a central insert of the metal of the base layer of the ingot, protected from the wide faces by two partitions in the form of plates, characterized in that, in order to improve the quality of the ingot, the partitions are made of metal of the peripheral layers of the ingot with a height equal to the height of the central insert and a thickness equal to 0.02 ... 0.05 distance between the wide edges and the inner wall of the mold, each partition is fitted with a gap in relation to the insert equal to I ... 2 thickness partitions. 2. The device according to claim 1, characterized in that 5 that the central insert is made in the head part with width b equal to h 1 + a, s, 7 -, - Gp) e a 1 120 mm - , 0- 0- - / С-, |. Go 293 K G, 1783 K - the width of the mold 1 in the head; - Linear thermal expansion coefficient h Guna SCH-15; -linear thermal expansion coefficient st. 20, temperature under normal conditions; steel melting point where a is the width of the cavity of the mold in the head part, mm; ttu - coefficient of linear thermal expansion of the mold material, L -; avsg - coefficient of linear thermal expansion of the material of the central insert, / С; Hz is the temperature of prn under normal conditions, 293 K; R | - The temperature of the most refractory partition material. TO; and the large edges of the central insert are made with a slope equal to the slope of the walls of the mold. 2