EA037177B1 - Method for producing semi-finished metallurgical products and shaped castings, and device for carrying out said method - Google Patents

Abstract

The invention relates to the metallurgical and foundry industry and can be used to produce metals and alloys under gas pressure and in a special gaseous medium. The device contains a furnace autoclave (1) and a casting autoclave (2), which are interconnected by a splitter (3), said splitter having a built-in gas-tight gate (4). The casting autoclave (2) is cut-off by a gas-tight gate (5). A pouring tube (6, 7, 20, 21, 32) is secured to a lower portion of a bottom plate (7) of a casting mould (8). In a capsule (9), in "high mode", casting of ingots (slabs, shaped castings), bimetal and three-layer ingots made of two or three alloy grades, and also conventional ingots, is carried out. The furnace autoclave (1) is designed with an induction furnace (12). A special feature of the invention is the use of a replaceable means for high-intensity cooling of a melt, which provides for a substantial increase in the output of the device and makes it possible to produce multi-layer ingots and shaped castings.

Description

(54) METHOD FOR PRODUCING METALLURGICAL BILLS, SHAPED CASTING AND DEVICE FOR ITS IMPLEMENTATION (31) 2015122307 (32) 2015.06.11 (33) RU (43) 2018.04.30 (86) PCT / RU2016 / 000218 (87) WO 2016/200289 2016.12.15 (71) (72) (73) Applicant, inventor and patent owner:

ELISEEV ANDREY VITALIEVICH (RU); RASHEV TSOLO VOLKOV (BG) (74) Representative:

Lomsky S.M., Ivaschenko O.I. (RU)

RU-C1-2127172

SU-A1 1482751

US-A-4616808

037177 B1

037177 Bl (57) The invention relates to the metallurgical and foundry industry and can be used for the production of metals and alloys under gas pressure and in a special gas environment. The device contains an oven autoclave (1) and a filling autoclave (2), interconnected by a cut-off device (3), in which a gas-tight gate (4) is built. The filling autoclave (2) is cut off by a gas-tight gate (5). The gating system (6, 7, 20, 21, 32) is attached to the bottom of the pallet (7) of the mold (8). In the capsule (9) with a high performance, the anti-gravity casting of ingots (slabs, shaped casting), bimetallic and three-layer ingots from two or three grades of alloys, as well as conventional ingots is carried out. The furnace autoclave (1) is made with an induction furnace (12). A feature of the invention is the use of a device for an indirect intense cooling of the melt, which provides a significant increase in the productivity of the device, and also allows the production of multilayer ingots and shaped casting.

The invention relates to the metallurgical and foundry industry and can be used for the production of metals and alloys under high gas pressure and in a special gas environment.

Known installation [Rasheval.A., PetkantchinL.T. Pat. 2001 / 6887.23 august 2001, Equipment for Production and Casting of Alloys, Republic of South Africa] for the production and casting of metals and alloys under high gas pressure or in a special atmosphere that can produce monolithic (mono) ingots, remeltable electrodes and steel castings doped with high concentrations of nitrogen and easily evaporating elements such as Ca, Pb, Mg, Zn and others. The installation includes oven and filling autoclaves, a hermetically sealed capsule with a sprue pipe, which can be hermetically made as a whole or hermetically self-contained with a hermetically sealed connection to each other. The furnace autoclave contains an induction furnace, and the casting one contains a set of molds for mono-ingots, remeltable electrodes or a casting mold. Furnace and filling autoclaves can have a common working space and, if necessary, autoclaves can be autonomously separated from one another using two gas-tight dampers. In the filling autoclave, a vertically sealed capsule with a metallurgical or casting kit moves, which can have an autonomous gas pressure (independent of the total operating pressure in the filling autoclave or a common pressure vessel formed by the furnace and filling autoclaves). The casting capsule contains a mold (mold), into which liquid metal is poured anti-gravity. The gating pipe is sealed to the capsule. The upper and lower movable platforms move along horizontal rail tracks, while the furnace and filling autoclaves are moved vertically with lifts. The disadvantages of the known installation are:

low productivity, since the ceramic gating tube has a low thermal conductivity, as a result of which you have to wait until the liquid metal (melt) in it crystallizes, and to start the next melting, it is necessary to disconnect both autoclaves;

limited assortment, excluding the possibility of producing two-layer and three-layer ingots and castings;

increased consumption of electricity, water, refractories and other consumable materials, since after filling the mold (mold), the induction furnace continues to operate;

a decrease in the efficiency of using a liquid charge, since crystallization in the pouring chamber limits all production processes;

replacement of expensive gating systems after each melting, since a solid alloy plug is formed in the refractory pipe.

The technical result to be achieved by the proposed method for the production of metallurgical billets, shaped casting and the device for its implementation consists in increasing productivity, reducing energy consumption and expanding the range of products.

The technical result in the implementation of the method is achieved by the fact that in the method for the production of metallurgical billets and shaped casting, according to which the furnace autoclave is filled with a liquid or solid charge, which is melted, and due to the difference in pressure through the gating pipe, the melt is fed into the mold or the mold of the casting autoclave, before by feeding the melt into the gating pipe between it and the mold pan, an indirect device for intensive local cooling of the melt with two replaceable sleeves is installed, which is used after filling the mold or mold with the melt and subsequent pressing with gas for local crystallization of the melt.

The device for intensive cooling of the melt can be supplied with water or other cooling agent.

An indirect device for intensive local cooling of the melt includes a replaceable conical refractory sleeve mating with a replaceable high-heat-conducting sleeve and a high-heat-conducting cooled sleeve. The gating pipe and the indirect device for intensive local cooling of the melt are the gating system.

When producing multilayer alloys, before feeding the melt, at least one metallurgical billet preliminarily located in the mold is heated.

To obtain metallurgical billets and shaped castings with different properties, the melt is treated with nitrogen under high pressure in an autoclave in an oven.

The technical result in the implementation of the device is achieved by the fact that in the device for the production of metallurgical billets and shaped casting, containing a movable furnace autoclave and a pouring autoclave with at least one mold or mold, are mated with each other by the corresponding gating pipe and the locking system, the mold tray and the end of the gating pipe are mated with a device for intensive cooling of the melt.

The mold pan is made with the installation of a replaceable conical refractory sleeve in it, mating with a replaceable high-heat-conducting sleeve and a high-heat-conducting cooled sleeve.

In a casting autoclave for producing multilayer alloys with the ability to move us- 1 037177, a heater is installed, located in the mold of a metallurgical billet, and a gas-permeable cover that closes the mold.

The number of furnace and filling autoclaves is determined by the volume of production.

The essence of the inventions is illustrated by drawings.

FIG. 1 shows a general view of the device for the production of metallurgical billets and shaped casting; in fig. 2 - device for intensive cooling of the melt; in fig. 3 is a diagram of the production of a bimetallic ingot; in fig. 4 is a diagram of the production of a three-layer ingot; in fig. 5 is a diagram of the production of a bimetallic slab.

The device for the production of metallurgical billets and shaped casting consists of movable, stationary and autonomous parts: an oven autoclave 1 and a filling autoclave 2, interconnected by a stationary shutter 3, in which a gas-tight gate is built in. 4. The casting autoclave 2 is cut off by a gas-tight gate 5. The gating pipe 6 is fixed to the bottom of the pallet 7 of the mold 8. The filling capsule 9 moves vertically by the mechanism 10, and moves horizontally together with the filling autoclave 2 on the trolley 11.

In capsule 9, with a high performance, the anti-gravity casting of ingots (slabs, shaped casting) of the type of bimetallic and three-layer ingots of two or three grades of alloys, as well as conventional ingots, is carried out. The furnace autoclave 1 together with the induction furnace 12 is moved vertically with a lift 13 to the stationary bayonet cutter 3, and horizontally moved by a trolley 14. The stationary cutter 3 connects the furnace autoclave 1 and the filling autoclave 2, and trolleys 11 and 14 move along the rail tracks 15 and 16 ...

In the furnace autoclave 1 there is an induction furnace 12, and in the casting autoclave 2 there is a set of molds 8 for ingots (casting molds) used in the production of mono-ingots, remelted electrodes, shaped castings, two or three-layer ingots or castings. The casings of autoclaves and capsules 9 can be low or high (in the case of bimetallic and three-layer ingots and slabs). Both autoclaves 1 and 2 can have a common working space, but they can also have a self-contained atmosphere. The capsule 9 in the casting autoclave 2 moves vertically with a casting mold or a casting kit for a mono-ingot, a bimetallic ingot, an ingot of three different metal layers or an ingot of three layers of two alloys. The capsule 9 has a sealed design with an autonomous gaseous medium, has a heater (s) 18 for heating the inner surface of the ingot (slab) 19 immediately before filling the mold 8. On the bottom of the capsule (in the pallet) 7, a highly heat-conducting sleeve 20 is mounted in contact with a copper water-cooled sleeve 21 Below them on the pallet 7, a hermetically sealed sprue pipe 6 is fixed.

The furnace autoclave 1 consists of a casing 22, a cover 23, connected by a bayonet connection 24.

The filling autoclave 2 consists of a casing with a lower part 25 and an upper part 26 connected by a bayonet connection 27. The capsule 9 has a lower part 28 and an upper part 29 connected by a bayonet connection 30.

The device for intensive cooling of the melt, in addition to the previously mentioned sleeves 20 and 21, contains a plastic sealing compound 31, a water flow sensor (cooling agent) and an automatic tap on the control panel, which turns on the maximum flow rate of cooling water (cooling agent) immediately upon the signal about filling the mold 8, but taking into account the time for pre-pressing the liquid metal for a tight seam with an ingot (slab) 19 and reducing the shrinkage cavity of the newly cast ingot.

The pallet 7 accommodates a replaceable refractory tapered bushing 32 (stone).

In the manufacture of alloys, a slab (semi-ingot) 19 is rigidly fixed in the mold 8, which occupies a part of the working space of the mold 8. A heater 18 is lowered into the free half of the mold 8 by a manipulator to heat the inner surface of the ingot (slab) 19. After reaching a predetermined temperature (different for different metals and alloys), the heater 18 rises and liquid metal 33 is fed from below to form the second part of the bimetallic ingot (slab) or the third part of the trimetallic alloy.

At its bottom, the pouring autoclave 2 has a built-in upper gas-tight gate 5. The stationary cut-off device 3 connecting the autoclaves 1 is fitted with a lower gas-tight gate 4. The induction furnace 12 is permanently mounted in the casing 22 of the furnace autoclave 1, which is mounted on pins 34 on a movable cart 14.

In the case of the production of a three-layer (Fig. 4) ingot (slab), the sequence of operation is similar to the production of bimetallic ingot (s).

When operating on a solid charge, the induction furnace 12 is filled with a solid charge, which is melted and processed under atmospheric conditions. The pouring autoclave 2 is prepared for melting on the installation itself or on the rail track 16. A stone 32 (tapered bushing) is mounted to the lower surface (Fig. 2) of the pallet 7, in contact with the highly heat-conducting bushing 20 (coated with plastic coating 31) and a highly heat-conducting cooled copper bushing is applied. 21, and then the gating pipe 6 is mounted. The copper sleeve 21 is connected on the control panel by two sensors with thermocouples embedded in the mold cover 8 to register the end of the metal casting process. Further, the slab (part of the ingot) 19 is mounted and rigidly fixed in the mold 8, the heater 18 descends next to it. After heating to the specified temperature of the inner surface of the slab 19, the heater 18 rises and a gas-permeable cover 35, a cover 29 of the capsule is placed after it 9, is fixed with a bayonet connection 30. The upper part 26 of the filling autoclave 2 is placed on the lower part 25 and fixed with a bayonet connection 27. The induction furnace 12 with the help of a trolley 14 moves along the rail track 15, is centered under the filling autoclave 2, is lifted by lifters 36 until it stops in a stationary the cutter 3 and is fixed by the bayonet connection 24. The liquid alloy 33 is processed under gas pressure, then the capsule 9 begins to descend in a controlled manner until the lower end of the sprue pipe 6 is immersed in the liquid metal. Thus, conditions are created for transportation due to the difference in pressure (ΔΡ = Ρ ₂ -Ρ1) in the combined working space of the furnace autoclave 1 and the pouring autoclave 2, and the liquid metal begins to flow anti-gravity through the gating pipe 6 into the mold 8. After filling the free volume molds 8 (Fig. 3) turns on the most intensive flow rate of cooling water (cooling agent) and local crystallization of liquid metal occurs in the unit (device) of controlled crystallization (Fig. 2). After local crystallization in the area of the sleeve 20, the gas-tight gate 5 is closed. The pressure P2 becomes higher than the pressure P ₃ , and the pressure of the gas P1 in the furnace autoclave 1 is reduced to atmospheric pressure. The bayonet connection 24 is opened, the furnace autoclave 1 is lowered to the final lower position with lifters 36, the furnace autoclave 1 is moved to the extreme left position and the furnace 12 is prepared to receive the charge for the next melting.

When operating on a liquid charge, the induction furnace 12 is loaded with a liquid charge, the furnace autoclave 1 is moved and centered under the filling autoclave 2. The sequence of other operations is similar to the option of working on a solid charge.

During the operation of the device, a method is implemented for the production of metallurgical billets and shaped casting to obtain the following ingots.

1. Monolithic conventional ingot.

The induction furnace 12 is heated to a temperature of 1580-1600 ° C. The pressure Pi in the furnace autoclave 1 and P2, P3, respectively, in the filling autoclave 2 and the capsule 9 are equalized within 20 s. After equalizing the pressure, high-nitrided ferrochrome is introduced, which is assimilated within 10 minutes. A negative differential pressure Δ создается = Ρ1-Ρ ₃ = 0.05 MPa is created in the capsule 9.

Within 6 s, the gating pipe 6 is filled, the differential pressure rises to 0.25 MPa, and the mold 8 is filled with melt and solidifies in about 10 minutes. Then the ingot is pre-pressed for about 6 minutes, the intensive cooling device is switched on, and after 2 minutes the casting ends. The pressure P ₃ over the ingot in the capsule 9 is maintained for 2 minutes at the level of 0.45 MPa. Then, within 15 s, the pressure P1 in the furnace autoclave 1 is removed and it moves under the charge for a new melting.

2. Bimetallic ingot (Fig. 3).

The operations are as in claim 1, only the mold 8 is different - a solid semi-ingot of alloy 19 is pre-loaded into it, heated to 100-150 ° C by the heater 18.

3. Three-layer ingot (Fig. 4).

The operations proceed as in clause 2, only two semi ingots 19 are laid in the mold 8.

4. Bimetallic slab (sheet) ingot (Fig. 5).

The operations proceed as in claim 1, but the solid semi-ingot 19 has the shape of a parallelepiped.

The device and method have the following advantages:

the adaptation of intensive controlled cooling of the gating channel section outside the gating ceramic tube 6 makes it possible to reduce the casting time and increase the productivity of the installation;

the device for intensive controlled cooling is located outside the gating pipe 6, which increases its service life tenfold;

the possibility of multiple use of the expensive gating system is created;

a wider range of products, including high-tech production of metallurgically welded bimetals and trimetals;

reducing the consumption of electricity, water, materials, etc. due to a shorter melting time; increasing the efficiency of work on a liquid charge, which is the basis for the competitiveness of the entire production;

reducing the duration of the harmful effect of the high-temperature mirror of the liquid alloy (1600-1700 ° C, radiation, dust, gases) on polished cylinders and polished guides of the columns of the lifting mechanism;

a significant reduction in the risk of industrial accidents due to an increase in the service interval of the gating system;

the device allows melting both under pressure and in atmospheric conditions, including in vacuum;

- 3 037177 a method for the production of metallurgical billets and shaped casting and a device for its implementation can be used for the production and casting of metals and alloys under gas pressure, in vacuum or under atmospheric conditions, as well as in a special gaseous environment for obtaining conventional (mono) ingots (slabs) ) monometallic, bimetallic, three-layer with two or three grades of metals or alloys, remelted electrodes; shaped castings, conventional, nitrogenous - AC, high nitrogenous - BAC steels alloyed with volatile elements such as calcium, lead, zinc, magnesium, manganese, etc., as well as non-ferrous metals and alloys.

Claims (5)

1. A device for the production of ingots and shaped casting, containing a movable furnace autoclave (1) and a filling autoclave (2) with at least one mold or mold (8), connected with a gating system (6, 7, 20, 21, 32) and a bayonet (30), characterized in that a replaceable conical refractory bushing (32) is installed in the lower part (7) of the mold or mold, and a device for the indirect intensive cooling of liquid metal is installed above the gating pipe (6), consisting of a replaceable heat-conducting bushing (20 ) with a coating surrounded by a heat-conducting cooled sleeve (21), while the capsule (9) inside the filling autoclave (2) has a sealed design with an autonomous gaseous medium. 2. A device according to claim 1, characterized in that a movable heater is installed in the pouring autoclave (2) for directed heating (18) of a metallurgical billet pre-located in a mold or mold (8), closed from above by a gas-permeable cover (35). 3. A method for the production of ingots and shaped casting by processing a liquid metal under a high gas pressure of nitrogen using a device according to claim 1, in which the furnace autoclave (1) is filled with a liquid or solid melted charge, which is heated to a predetermined temperature of the liquid metal, after which, after due to the difference in pressure, through the gating pipe, the liquid metal is fed into the mold or the mold of the casting autoclave (2), characterized in that between the gating pipe and the bottom of the mold or mold is installed a device for the indirect intensive cooling of the liquid metal, consisting of a replaceable heat-conducting sleeve (20) with coating, covered by a heat-conducting cooled sleeve (21), while the capsule (9) inside the pouring autoclave (2) has a sealed design with an autonomous gaseous medium, in which, after filling a mold or a mold with liquid metal and pressing with gas, directed local crystallization of liquid metal is carried out above the sprue pipes in the zone of an indirected cooling device. 4. The method according to claim 3, characterized in that water or another cooling agent is supplied to the device for the indirect intensive cooling of the liquid metal. 5. A method according to claim 3 or 4, characterized in that at least one metallurgical blank is pre-installed in the mold or mold, which is heated before the liquid metal is fed.