RU2406953C1 - Shaft reverberating furnace for metal remelting - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: shaft-reverberating furnace for re-melt of metal, mainly, aluminium scrap, consists of shaft, of melting chamber, of collecting bath limited with hearths and walls and equipped with two roofs, of tap hole, of swinging runner, of gas duct and of welded frame. In the shaft there are two working windows and a slag window for fast charging from two places; there is also a door of the working window in the shaft with a lifting and dumping device forming a L-shape lock. Two gas burners in the melting chamber and two gas burners in the collecting bath are installed in the furnace. The furnace can operate on natural or forced draught with system of powder-gas cleaning. The furnace is built in the iron box equipped with heat insulation between the box and each wall; heat insulation consists of three layers of sheet asbestos cardboard. Hearths of the melting chamber and collecting bath are made out of hearth blocks MKRS-45 № 1 laid on four layers of asbestos cardboard and pad out of chamotte powder mixed with chips out of light-weight brick, which maintains heat preventing its loss to the frame. The furnace has the swinging runner with a rotary pan for successive tapping metal melted in the furnace into the casting equipment in the service sector at angle of 130°. Quick-change ribbon-type bricks in metal boxes are laid in the furnace; bricks can be easily replaced with new ones in case of wear without dismantling the end and two side walls. The roofs above the melting chamber and collecting bath are enveloped with two layers of heat insulation; a layer out of refractory heat insulating mats is laid over them.

EFFECT: raised efficiency and re-melt of scrap unsorted from foreign inclusions.

5 cl, 6 dwg

Description

The invention relates to ferrous metallurgy, and in particular to smelting units for remelting secondary aluminum scrap and waste aluminum alloys into ingots and ingots. A more correct name of the furnace should be: "A shaft-reflective furnace is a two-chamber countercurrent furnace with a shaft charge heater." The furnace can be used for refining, producing alloys, averaging the chemical composition of scrap.

A known analogue is a shaft-reflective furnace (see V. A. Grachev. Foundry furnaces. - M .: MGOU, 1994, p. 464-465, fig. 12.9), containing, as in the declared furnace, a shaft, two chambers separated by a baffle with a hole, gas burners.

The disadvantages of this furnace are:

1. The lack of external thermal insulation of the furnace, reducing heat loss to the external environment.

2. The furnace does not have a notch and a trough for spilling metal. The metal is manually scooped from a pocket with a ladle and poured.

3. The furnace does not have a dust and gas cleaning system and during operation will pollute the environment with harmful emissions.

4. From the description of the furnace it follows that it is equipped with only two burners. This is clearly not enough to ensure a high rate of penetration of the charge and maintaining a forced melting mode. Due to the above disadvantages, the furnace cannot provide a solution to the technical problem.

A known analogue is a mine smelting furnace (information source of the USSR AS No. 549661, class F27B 1/00), containing, as in the declared furnace, a mine, a piggy bank, a burner, a smoke exhauster, a tap hole and a gas duct.

The furnace is designed for melting aluminum alloys, primary aluminum, waste and has the following disadvantages:

1. One burner cannot provide forced melting mode.

2. The lack of external thermal insulation of the furnace, reducing heat loss to the external environment.

3. The furnace does not have a dust and gas cleaning system and during operation will pollute the environment with harmful emissions.

4. The furnace uses a stationary chute to drain molten metal.

Due to the above disadvantages, it is impossible to obtain a technical result.

A known analogue is a melting furnace with a shaft charge heater (information source - M.S. Shklyar. Furnaces of secondary non-ferrous metallurgy. - M .: Metallurgy, 1987, pp. 186-187, Fig. 78), which is the closest (prototype), containing a mine, an alloy chamber (melting chamber), a piggy bank, (storage bath) with an inclined hearth, a chimney, burners, a drain outlet. I believe that the oven, taken as a prototype, has the following disadvantages:

1. From the drawing and description of the furnace it follows that the external thermal insulation of the walls, vaults, as well as the piggy bank (storage bath) is insufficient.

2. The furnace is not highly productive;

3. The furnace has satisfactory tightness.

4. The furnace uses a stationary chute for draining molten metal;

5. The furnace does not have a dust and gas cleaning system and during operation will pollute the environment with harmful emissions.

Due to these shortcomings, it is impossible to obtain a technical result.

The objective of the invention is the creation of a high-performance gas shaft reflective furnace for remelting aluminum scrap of a simple design, hermetic, which allows to reduce emissions of harmful gases into the atmosphere, reduce metal and heat losses into the environment, as well as increase its life and introduce a rotary trough into the furnace.

EFFECT: developed furnace is simple in design, having a rotary trough, hermetic, having a long service life, highly productive, allowing to use scrap unsorted from foreign inclusions, to reduce heat loss to the environment due to special thermal insulation, to conduct the remelting process on natural and artificial traction with a dust and gas cleaning system, which makes it environmentally friendly.

The specified technical result is achieved due to the fact that in a melting furnace with a shaft heater of a charge containing a shaft, a melting chamber, a storage bath, limited by hearths and walls, having two arches, a chimney, burners, a drain drain, according to the invention, the housing is placed on a welded frame having in the upper part a heat-insulating layer of three rows of sheet asphalt board, a thick steel sheet laid on two heat-insulating layers of concrete with a filler - fireclay chips. The heat-insulating layer, consisting of three rows of sheet asphalt board, and two heat-insulating layers of concrete with a filler - fireclay chips - can reduce heat loss.

In addition, the hearths of the melting chamber and the storage bathtub are made of MKRS-45 No. 1 hearth blocks laid on four layers of asbestos-cardboard, and have a knockout made of fireclay powder mixed with lightweight brick crumbs. The service life of the furnace is increased due to the use of hearth blocks MKRS-45 No. 1, which have high refractoriness and resistance (the service life is 6-7 years according to practical data). By using MKRS-45 No. 1 blocks instead of ordinary piece products, the number of joints can be reduced, which reduces gas permeability and increases the slag resistance of the lining; get cost savings, because the process of prefabrication of piece refractories disappears, speed up the construction process and reduce the proportion of manual labor. Thermal insulation, consisting of four layers of asbestos board and chamotte tamping, mixed with lightweight brick chips, allows you to further maintain the temperature of the metal in the melting chamber and storage tank.

It should be noted that, in comparison with the prototype, the proposed furnace has two working windows: the upper one in the shaft and the lower one in the melting chamber, through which the charge is loaded from two places. Due to the above mentioned in the process regulations, more time is devoted to smelting, the furnace smelts more aluminum scrap. The charge loaded into the furnace moves downward, and the hot flue gases move upward, heating the charge. The counterflow principle allows to make fuller use of the heat obtained during combustion, while obtaining high thermal efficiency.

At the same time, the shaft-reflective furnace for remelting aluminum scrap has two gas burners in the melting chamber and in the storage bath. This arrangement of the burners allows you to achieve a high melting speed, reduce fumes (according to practical data), and also makes the furnace highly productive, allowing you to conduct a forced melting mode.

At the same time, the shaft-reflective furnace for remelting aluminum scrap has a rotary chute, which has a rotary bowl in its design, which makes it possible to sequentially pour metal deposited in the furnace into casting equipment located in the service sector with a 130 ° angle. During casting of molten metal, the swivel chute is closed by a lid, which reduces heat loss and gas emission, improves working conditions for staff.

Moreover, a steel box is welded to the furnace frame, having thermal insulation between it and each wall, consisting of three layers of sheet asbestos board. This design solution significantly reduces heat loss to the environment.

It is important to note that the arches of the melting chamber and the storage bath have a double refractory heat-insulating coating and a layer of refractory heat-insulating mats is laid on top of them. This further reduces heat loss from the furnace.

In addition, the furnace has a flap of the upper working window with two welded steel pipes and a triple insulating layer of asbestos board lined with lightweight refractory brick protruding 50-60 mm beyond the frame and forming a reliable “L-shaped lock” when closing, which helps to reduce fumes and reduce heat loss.

Further, the presence of a working and slag windows in the melting chamber and a worker in the storage bath allows the furnace to be remelted of scrap unsorted from foreign inclusions, as the attachments (cast iron and steel rings, liners, bushings, studs, pushers, valves, etc.) do not fall into the molten metal, and also load the charge without ferrous metal attachments into the working window of the storage bath.

Finally, the furnace includes a dust and gas cleaning unit, which allows the remelting process to be carried out on natural and artificial draft with the cleaning of flue gases from harmful substances and dust.

Introduction to the furnace design of the above devices, materials, etc. provides a solution to the problem.

Figure 1 - General view of the furnace.

Figure 2 is a section aa of the furnace.

Figure 3 is a section bB of the furnace melting chamber (view of the window in the partition).

Figure 4 - section bb furnace (view of the burner and the explosion valve).

Figure 5 - section GG furnace (longitudinal section).

Figure 6 is a drawing of the installation of dust and gas cleaning.

The proposed furnace contains a housing 1 mounted on the frame of the furnace, formed by brickwork from fireclay bricks (figure 1). The frame 2 has in the upper part a heat-insulating layer 3 of three rows of sheet asbestos board, a thick steel sheet 4, laid on two heat-insulating layers of concrete with a filler - fireclay chips. The heat-insulating layer 3 of three rows of sheet asphalt board and two heat-insulating layers of concrete with a filler - fireclay chips - can reduce heat loss. The frame 2 is welded from a steel sheet 10 mm thick. In the lower part of the frame, the first heat-insulating layer 5 of concrete with a filler is poured, which has welded double-row reinforcement 6 from a bar with a diameter of 12 mm (Fig. 3). In the upper part of the frame 2 there is a second heat-insulating layer 7 of concrete with a filler, which has a row of channels No. 14 (8) inside. The hearths of the melting chamber 9 and the storage bath 10 are made of hearth blocks 11 MKRS-45 No. 1, laid on four layers of asbokarton 12, and have a tamping 13 of fireclay powder mixed with lightweight brick crumbs. The service life of the furnace is increased due to the use of hearth blocks MKRS-45 No. 1, which have high refractoriness and resistance (the service life is 6-7 years according to practical data). Using blocks MKRS-45 No. 1 (thickness 300 mm, width 400 mm, length 1000 mm) instead of conventional piece products, the number of joints can be reduced, which reduces gas permeability and increases the slag resistance of the lining; get cost savings, because the process of prefabrication of piece refractories disappears, speed up the construction process and reduce the proportion of manual labor. The seams between blocks MKRS-45 No. 1 are filled with finely ground dry chamotte powder, and the author achieved even better results when the chamotte powder poured into the slots of the hearth blocks and the inclined platform was filled with liquid glass in the upper part and then “flush” with the upper plane bottom and inclined platform with TRIUMF refractory adhesive mastic. As a binder, a refractory solution is used, consisting of refractory clay (21%), fireclay powder (75%), water glass (3%) and phosphon (aluminochromophosphate mixture, 1%). The thickness of the seams is 1-2 mm, thermal expansion joints are not laid out.

Thermal insulation, consisting of four layers of asbestos board 12 and a tamping 13 made of fireclay powder mixed with lightweight brick chips, allows you to further maintain the temperature of the metal in the melting chamber 9 and the storage bath 10.

The melting chamber 9 and the storage bath 10 are limited by hearth blocks 11 and walls 14. The walls 14 of the furnace are laid out in two bricks, the inner layer is made of fireclay bricks SHA-1, No. 5 GOST 8691-73, and the outer layer is made of fireclay lightweight ШЛБ-0, 9, No. 5. Above the storage bath 10, 500 mm deep, a large arch 15 is assembled, supported by heel bricks 16 (ША - 1 No. 67), lined in the side walls 14. A small arch 17 is made above the melting chamber 9 and also rests on the heel bricks 16 (ША - 1 No. 67). The large vault 15 and the small 17 are assembled from fireclay bricks SHA - 1 No. 22, 23. It is important to note that the large vault 15 and the small 17 of the furnace have a double refractory heat-insulating coating 18 and a layer of refractory heat-insulating mats 19 is laid on top of them (Fig. 5), and “flush” with the level of walls 14, fireclay chips were bombarded. This further reduces heat loss from the furnace.

A steel box 20 is welded to the frame 2 of the furnace, having thermal insulation between it and each wall, consisting of three layers of sheet asphalt board 21 (Fig. 3). This design solution significantly reduces heat loss to the environment.

It should be noted that the countercurrent principle is used in the proposed reflective furnace for remelting aluminum scrap. The charge loaded into the furnace moves downward, and the hot flue gases move upward, heating the charge. The counterflow principle allows to make fuller use of the heat obtained during combustion, while obtaining high thermal efficiency. Compared with the prototype, the proposed furnace has two working windows: the upper 22, located in the upper part of the shaft 23, and the lower 24 in the melting chamber 9, through which the charge is loaded from two places. Due to the above mentioned in the process regulations, more time is devoted to smelting, the furnace smelts more aluminum scrap. In the melting chamber 9 there is a slag window 25, closed by a door 26, which is intended for cleaning, removing iron impurities, slag. In the storage bath 10 there is a working window 27, closed by a door 28, which is designed to remove iron impurities, slag, mixing liquid metal and the addition of flux. The melting chamber 9 and the storage bath 10 communicate with each other through the window 29 in the partition 30. Under the melting chamber 9 is made with an inclination of 6 ° from the back wall to the front and 1 ° from the side wall to the window 29 of the partition 30. Under the storage bath 10 is made at an angle of inclination of 3 ° from the back wall to the front with the outlet notch 31. Explosion valves 32 with a cross section of 200 × 250 mm are placed in the walls of the melting chamber 9 and the storage bath 10. The third explosive valve 33 with a cross section of 300 × 250 mm is installed on the gas duct at the point of connection to the shaft 23 of the furnace.

At the same time, the reflective furnace for remelting aluminum scrap has two gas burners 34 in the melting chamber 9 and the storage bath 10. This arrangement of the burners 34 allows one to achieve a high melting speed, reduce fumes (according to practical data), and also makes the furnace highly efficient, allowing lead forced melting mode. Natural gas is burned in four burners 34 with forced air supply of the GGV-MGP type (series 5.905 - 14 gas burner devices, recommendations for use). GGV-MGP-50 burners with a rated heat output of 577 kW and a torch length of 450 mm are installed in the melting chamber 9 and the storage bath 10. Burners are installed at an angle of 15 ° to the horizon. In addition, the burners 34 of the melting chamber 9 are located along the longitudinal axis of the melting chamber 9, and the burners of the storage bath 10 are at an angle of 60 °. Burner stones 35 of all burners are made individually from a high alumina mortar. Burners are lined with a special refractory ramming mass of their own design, having the following composition:

Chamotte mortar МШ 39 ТУ 14-199-119-200;

Technical lignosulfonate TU 13-0281036-89;

Powder ground clay PHB TU 1522-009-00190495-99;

Foscon (aluminochromophosphate mixture) TU 2149-150-10964029-01;

Water

For ignition of burners, an intermediate-pressure injection igniter is multi-torch, the diameter of the fire nozzle is 27 mm.

The reflective furnace for remelting aluminum scrap has a rotary trough 36, which has a rotary bowl 37 in its design, which allows the metal deposited in the furnace to be sequentially poured into casting equipment (for example, casting ladle 38, casting conveyor 39) located in the service sector with an angle of 130 ° (filling equipment is shown only in figure 2). The rotary chute 36 during casting of molten metal is closed by a hinged lid, which reduces heat loss and gas generation, improves working conditions for staff. The hinged lid is attached to the groove 36 using three loops 40.

For the molten metal to flow into the groove 31 and for the convenience of cleaning the groove in the process of removing attachments and slag from the bottom of the storage bath 10, there is a recess 41 in front of the groove 31, made in the hearth block by a “grinder” during the lining of the furnace. Frame 2 with a furnace is mounted on a reinforced concrete foundation (not shown).

Letka 31 is drilled in summer brick 42. Summer brick 42 is placed in a metal box of summer brick and, when laying the wall, it is laid in a niche and fixed with wedges in it (not shown).

When replacing a worn summer brick 42, the metal box of the summer brick with the inside brick 42 is removed from the niche, the old summer brick 42 is removed, the new summer brick 42 and the metal summer brick with the new summer brick 42 installed in it are inserted into the metal box of the summer brick 42 put in a niche and fixed with wedges.

The furnace has a shutter 43 of the upper working window 22 with two welded steel pipes 44 and a triple insulating layer of asbestos-cardboard, lined with lightweight refractory brick 45, protruding 50-60 mm behind the frame and forming a reliable “L-shaped lock” when closing, which helps to reduce fumes and reduce heat loss. The reflective furnace for remelting metal has a manual device for raising and lowering the shutter 43 of the upper working window 22, which consists of two copiers 46, four pulleys 47, two cables 48, two counterweights 49 and the shutter 43. The shutter 43 consists of a welded frame and two nozzles 44 relies on two copiers 46, and with the help of the actuator, the shutter 43 can move up and down, opening and closing the working window 22. The shutter 43, when closing the working window 22, rests on the bottom on a steel sheet of the loading platform 50. The shutter has a welded back wall with two handles. The tightness of the shutter 43 of the working window 22 of the furnace is ensured by the entrance part of the copiers 46, which has an angle of 40 degrees.

A similar design, but without welded nozzles, copiers, counterweights, etc. have other oven doors. To open and close the doors in their design, hinges are provided. Doors, when closed, form a reliable “L-shaped lock”, which helps to reduce waste and reduce heat loss.

The flue gases generated by the combustion of gas from the shaft of the furnace enter the bog 51. In the bog 51 there is a damper 52 that regulates the draft (artificial and natural).

The furnace includes a dust and gas cleaning unit, which allows the process of remelting on artificial traction to clean flue gases from harmful substances and dust. When using a dust and gas cleaning installation, the process becomes environmentally friendly (the dust and gas cleaning installation is conventionally shown in figure 1 - position 53, and a General view - figure 6). The dust and gas cleaning installation is a prefabricated steel cylindrical body 54, in the lower part of which there is a rotary loading grill 55 with holes. Above the rotary loading grill 55 is a loading pipe 56 (Fig.6). In the upper cylindrical part of the housing 54, rotating bag filters are located that trap the dust particles from the flue gases. At the top of the casing 54 there is a cover 57, which is fastened with eight bolts and eight nuts to the upper flange of the casing 54 of the dust removal installation. A bracket 58 is mounted on the lid 57, on which a blower 59 with an electric motor 60 is located. The servicing platform 61 for the dust and gas cleaning installation is supported by four supports 62 and has a ladder 63 on the left. The processed adsorbent and dust are collected in the conical part of the housing 54. The cleaned gases from the furnace are fed into the installation dust and gas cleaning through the pipe 64. Up to the pipe 64, a DN-9u smoke exhauster (not shown) is installed. Bag filters rotate from a drive consisting of an electric motor 65, a clutch 66, a worm gear 67, a rotating plate 68. Dust and spent adsorbent are collected in the conical part 69 of the dust and gas cleaning, and they are unloaded through the pipe 70. When natural draft, when the gate 71 on the camera mixing 72 is closed, the gate 73 behind the dust removal installation 53 is closed, and the gate 74 on the bogie is open, the flue gases through the bogie 51 and the chimney 75 are removed to the atmosphere. With natural draft, the furnace works when repairs or maintenance are being carried out at a dust and gas treatment plant. The borovka branch, going to the exhaust fan (not shown), has a mixing chamber 72 in which two gates are installed: one of which 71 closes or opens the supply of exhaust gases to the exhaust fan, the other 76 regulates the supply of fresh air to dilute the combustion products (Fig. 1 )

After cleaning from dust and harmful gases, the combustion products through a metal return duct 77 are pumped by a blower 59 into the chimney 75. During artificial draft, the vacuum is generated by the DN-9u exhaust fan, which has an operating temperature of up to 250 ° C, while the flue gases at the inlet to the hog have a temperature of 650-750 ° C. In order to reduce the temperature of the flue gases, a mixing chamber 72 is installed in which the hot flue gases are mixed with the air of the workshop, as a result of which the temperature of the flue gases becomes 150-200 ° C. The dust and gas purification produced by the industry has a wide range of purified harmful substances in flue gases, and the degree of purification is 70-97%. As a rule, they have a service platform on which the operator climbs the stairs 63 (as shown in Fig.6). Workers loading the charge into the furnace through the upper working window 22, rise to the service platform 78 via stairs 79. It should be noted that the steel box 20 is reinforced from the outside by horizontal 80 and vertical channels 81.

The furnace operates on natural draft as follows. The smelter of metal and alloys opens the gate 74 and the control valve 52, and the gate 71 and 73 are closed, while the thrust should be 2-20 daPa. Burners 34 are turned on and the furnace is calcined according to the technological schedule of calcination, depending on the type of repair. The shutters of the working windows: upper 22 and lower 24 open and metal and alloy smelters load unrefined aluminum scrap at ambient temperature into the calcined furnace. The flame of two gas injection burners 34 (FIG. 2) heats the scrap to the melting temperature. The metal melts in the melting chamber 9 and flows through the window 29 of the partition 30 into the storage tank 10 of the furnace. The temperature of the liquid metal in the storage bath 10 is supported by two burners. During operation of the furnace, heat is accumulated in the large arch 15 and the small arch 17, from where it is reflected on the metal. Coating layers of vaults 15 and 17, heat-insulating mats 19, heat insulation of walls, hearth, heat insulation of the furnace frame, knockout made of fireclay powder mixed with lightweight brick crumbs, and four layers of asbestos-board provide high thermal insulation of the melting unit. At the same time, the concrete frame of the furnace 2 with the filler - fireclay chips - provides additional thermal resistance to the heat flow coming from the bottom of the melting chamber 9 and the storage tank 10 down. The thermal efficiency of the furnace is above 65%. During the melting process, the scrap melts, the moisture in it evaporates, decomposing into oxygen and hydrogen, and all inclusions remain on the bottom of the melting chamber 9, the melting temperature of which is higher than the aluminum alloy. These wastes (alterations: cast iron and steel rings, liners, bushings, studs, pushers, valves, etc.) do not fall into the molten metal, since at the end of smelting they are removed through the slag window 25 with a scraper from the bottom surface of the melting chamber 9 to slag. After the molten scrap loaded into the furnace is completely melted, molten metal is processed with flux, the metal is thoroughly mixed in the storage bath 10 and the alloy spectral analysis laboratory confirms the grade of the alloy obtained, the metal castors bring the end of the swivel trough 36 to the center of the casting ladle 38. Next, the metal fill opens the channel 31 of the furnace and produces pouring liquid metal into the casting ladle 38. Thus, liquid metal from the furnace can be poured through the rotary chute 36 sequentially into the casting equipment laid in a sector with an angle of 130 ° (for example, still in the casting conveyor 39). After casting from a liquid metal furnace, metal and alloy smelters open the door 28 of the working window 27 and clean the bottom of the storage bath 10 from slag and incidentals accidentally falling onto it, also clean the bottom of the melting chamber 9 from slag, attachments, and also the window 29 of the partition 30 from slag and nastily. The operation of the furnace on artificial draft is as follows. The smelter of metal and alloys closes the gate 74, and the control valve 52 and the gate 71, 73, 76 are open. The operations are carried out the same as when melting on natural draft, only the flue gases from the furnace pass through dust and gas treatment. The difference is that before loading the charge, the adsorbent (“fluff” lime and activated carbon) is loaded into the furnace and the dust and gas treatment unit 53 is turned on and turned on. The combustion products, having passed part of the boron and mixing chamber 72, are awakened (diluted) in it by the air of the workshop, then diluted flue gases are pumped by the DN-9u exhaust fan (not shown) into the nozzle 64 and a layer of adsorbent passes under pressure, a "fluidized bed" is formed, as a result, harmful substances in flue gases are adsorbed by slaked lime and activated carbon.

After cleaning the flue gases from harmful substances, they are cleaned of dust in bag filters located in the upper part of the cylindrical housing 54 (Fig.6). The purified gases by the blower 59 are pumped into the chimney 75 and discharged into the atmosphere. Once every three days, the spent adsorbent is discharged through the pipe 70 into a metal container and transported to a dump.

Flue gas cleaning makes the smelting process environmentally friendly. After casting the liquid metal, the storage bath 10 is cleaned of slag and incidentals accidentally falling into it, the melting chamber 9 is cleaned of slag and additives, and also the window 29 of the partition 30 is free of slag and slabs, the tap hole 31 is closed and the cycle repeats. So, the proposed furnace is simple in design, hermetic, having a long service life, high-performance, having low heat loss to the environment due to special thermal insulation, the dust and gas cleaning unit included in the furnace makes the process environmentally friendly.

Claims (5)

1. Shaft-reflective furnace for remelting a metal, comprising a shaft housing, a melting chamber, a storage bath, bounded by hearths and walls and having two arches, a chimney, burners, a drain outlet, characterized in that the body is placed on a welded frame having in the upper part a heat-insulating layer of three rows of sheet asbestos board and a thick steel sheet laid on two heat-insulating layers of concrete with a filler - fireclay chips, while the furnace is equipped with dust and gas cleaning and a swivel chute with a rotary bowl to ensure sequential casting of the metal deposited in the furnace into casting equipment located in the service sector with an angle of 130 °, and with a lid covering the swivel chute when casting liquid metal. 2. The furnace according to claim 1, characterized in that the hearths of the storage bath and the melting chamber are made of hearth blocks MKRS-45 No. 1, laid on four layers of asbestos-cardboard, and are tamped with fireclay powder mixed with lightweight brick crumbs. 3. The furnace according to claim 1, characterized in that it has two working windows for loading the mixture from two places, while the upper window is made in the mine, and the lower one is in the melting chamber. 4. The furnace according to claim 3, characterized in that the upper working window has a shutter with two welded steel pipes and a triple insulating layer of sheet asbestos board, lined with lightweight refractory brick protruding 50-60 mm beyond the frame and forming a L-shaped lock when closed to reduce fumes and reduce heat loss. 5. The furnace according to claim 1, characterized in that the arches of the melting chamber and the storage bath have a double refractory heat-insulating coating and a layer of refractory heat-insulating mats is laid on top of them.

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