CN207936753U - A kind of double helix embeds hot magnesium vacuum reduction stove in Exciting-simulator system electromagnetic induction - Google Patents

Abstract

The utility model relates to a double-helix embedded excitation type electromagnetic induction internal heat magnesium vacuum reduction furnace, which comprises a furnace body. The furnace body is provided with a plurality of cylindrical material baskets arranged in a honeycomb shape, and double excitation coils are embedded in the wall of the basket body. , the excitation coil is introduced from the bottom of the basket wall, spirals up, and is drawn out from the top. After the excitation coils of multiple baskets are connected in parallel, they are drawn out of the furnace through the insulating sealing device on the furnace body to connect with the power supply device, and the electric energy is transmitted without contact. The feeding basket is used to heat the reaction furnace material, and the heating element will generate heat uniformly as a whole, and will not be damaged due to local high temperature. It mainly solves the problems of serious excitation coil loss, large leakage inductance and high cost of reactive power compensation capacitors in the existing electric heating internal heating vacuum reduction furnace. High efficiency; mainly used in the production of magnesium, lithium, strontium, calcium and other high vapor pressure metal thermal reduction methods.

Description

A double-helix embedded excitation type electromagnetic induction internal heat magnesium vacuum reduction furnace

technical field

The utility model relates to the technical field of vacuum metallurgical equipment, in particular to a double-helix embedded excitation type electromagnetic induction internal heat magnesium vacuum reduction furnace, which can be used for thermal reduction to prepare high vapor pressure metals such as magnesium, lithium, strontium and calcium.

Background technique

Metals with high vapor pressure such as magnesium, lithium, strontium, and calcium can be prepared under vacuum conditions by thermal reduction. At present, in the field of metal magnesium production, the widely used reduction equipment is to directly heat the reduction tank made of heat-resistant alloy with gas or the like. This method is limited by the structure and material properties of the reduction tank, the reaction temperature is low, the heat transfer is slow, the energy consumption is high, and a large amount of expensive nickel-chromium alloy is consumed due to the oxidation of the reduction tank.

The electric internal heating vacuum reduction furnace can overcome the problems of high energy consumption and reduction tank consumption of the external heating reduction furnace. The electric internal heating vacuum reduction furnace mainly solves the problem of increasing the speed of heat transfer in the charge and increasing the production efficiency. For example, a utility model patent ZL 96247592.0 discloses an induction heating reduction magnesium smelting device. In this scheme, an induction coil is wound on the outer wall of the reduction tank, and the material is heated by electromagnetic induction through the induction coil connected with an induction power supply. The patent application with publication number CN105018730A discloses an electromagnetic induction internal heating type metal magnesium vacuum reduction furnace. In this scheme, a rectangular iron core is set in the furnace body, one long side passes through the central channel of the material basket, and the other side is wound with a copper coil, and the material is heated by electromagnetic induction through the connection of the lead end of the copper coil to the power supply, but both There are problems such as relatively serious loss of the excitation coil, large leakage inductance, and high cost of the required reactive power compensation capacitor.

Utility model content

The purpose of this utility model is to provide a double-helix embedded excitation type electromagnetic induction furnace to solve the technical problems of serious excitation coil loss, large leakage inductance and high cost of reactive power compensation capacitors in the existing electric heating internal heating vacuum reduction furnace. Internal heat magnesium vacuum reduction furnace.

In order to solve the problems of the technologies described above, the technical solution adopted in the utility model is:

A double-helix embedded excitation type electromagnetic induction internal heat magnesium vacuum reduction furnace includes an upper furnace shell, a lower furnace cover, a material basket, a platform, a support frame, a crystallization chamber and a cooling device. The material basket is composed of a basket body, an excitation coil, Composed of metal baffles and steel strips, a single spiral groove is opened on the outer wall of the basket, and a single spiral magnesium steam overflow seam is opened on the outer wall of the basket, which is arranged parallel to the groove, and the excitation coil is arranged in the groove , the cross-section of the conductor of the exciting coil is rectangular, and it is a double helical coil and is wound. Outside the groove, there are several air holes on the metal baffle, and the upper and lower sides of the metal baffle are folded outwards, and the steel belt is set close to the outer side of the folding, and the upper and lower sides of the steel belt are welded to the wall of the basket. Above, the upper furnace shell is closed on the lower furnace cover to form a furnace body, the platform is horizontally arranged at the bottom of the furnace body, and is supported and fixed by a support frame, and several material baskets are arranged on the platform in a honeycomb shape, and are located in the furnace body, and The excitation coils of several baskets are connected in parallel and then led out of the furnace through the insulating sealing device on the furnace body to be connected with the power supply device. The bottom is provided with a coarse suction port, and is located on both sides of the furnace body separately from the crystallization chamber, and the cooling device is arranged on the outer wall of the crystallization chamber. The surface of the basket is cut with magnesium vapor overflow seams parallel to the excitation coil and arranged staggeredly, which increases the resistance of the basket, reduces the calorific value, and facilitates the diffusion of the reduced magnesium vapor to meet the needs of uniform distribution of the temperature field of the charge. .

Further, an insulation layer is provided on the inner wall of the furnace body and the metal steam channel, and a gap is left between the furnace body and the material basket to facilitate loading and unloading.

Furthermore, the insulating layer is a ceramic material layer. Ceramic insulating material is a kind of inorganic non-metallic material made of natural or synthetic compounds after forming and high-temperature sintering. It is the material with the best rigidity and highest hardness among engineering materials. It generally has a high melting point (mostly above 2000 ° C) , and has excellent chemical stability at high temperatures; ceramics are also good heat insulating materials; at the same time, the coefficient of linear expansion of ceramics is lower than that of metals, and ceramics have good dimensional stability when the temperature changes.

Furthermore, the cooling device is a water cooling jacket.

When working, the pelletized reducing charge is loaded in the material basket and directly contacts with the material basket. The high-frequency alternating current applied to the excitation coil by the power supply unit generates an alternating magnetic field in the basket. This induces a current in the metal basket. The heat generated by the electric current induced in the charging basket heats the charge through conduction and radiation. Through this electromagnetic induction process, electric energy is transmitted to the material basket without contact to heat the reaction charge. The heating element (material basket) generates heat uniformly as a whole, and is made of thicker heat-resistant steel plate, which conducts heat quickly, and the temperature distribution of the heating element itself is uniform. , will not be damaged due to local high temperature. During the reduction process, the coarse pumping port is used to pump air during the rough vacuuming stage. Since the rough pumping port is arranged at the bottom of the furnace body, the floating dust in the furnace gas will not be deposited in the crystallization chamber and reduce the purity of crystalline magnesium. When a higher vacuum degree is reached, the gas flow rate is very low at this time, the rough pumping port is closed, and the vacuum is drawn from the fine pumping port passing through the crystallization chamber. The entire heating element is in a vacuum environment, and the force is very small, and it is not easy to oxidize due to the protection of the vacuum.

Compared with the prior art, the utility model has the following advantages:

1. There is an insulation layer between the furnace shell and the high-temperature reducing material, and the temperature of the furnace shell is only slightly higher than the ambient temperature. Therefore, the furnace body only needs to be made of ordinary carbon steel.

2. The heating element (basket) is a cylindrical object made of a certain thickness of heat-resistant steel plate (reduced tank material or 310S stainless steel with the existing process), which has high structural strength and is not easy to be damaged during loading and unloading of the charge.

3. The double-strand excitation coil is buried inside the material basket, and the space between the excitation coil and the wall of the material basket is filled with high thermal conductivity ceramic insulating material, the coupling efficiency is high, the heat is gathered inside the heating body, and the external heat dissipation is extremely small, which makes the heating The whole body (basket) heats up evenly, and the material basket is made of thicker heat-resistant steel plate, which conducts heat quickly, and the temperature distribution of the heating body itself is uniform, and it will not be damaged due to local high temperature. The entire heating element is in a vacuum environment, and the force is very small, and it is not easy to oxidize due to the protection of the vacuum. Therefore, the heating temperature in the furnace can be higher than that of the Pidgeon method, which greatly improves the reduction reaction speed and the utilization rate of the charge.

4. A single reduction furnace can arrange multiple reduction tank baskets (made of heat-resistant steel) in a honeycomb shape, so that there is sufficient heat dissipation area and short heat transfer distance, so as to ensure the heat dissipation when the volume of the basket is large. The speed of transmission will not be reduced, and the larger the single furnace, the more baskets are arranged, which reduces the relative surface area, improves the production capacity of a single furnace, and has high thermal efficiency.

5. The material basket is placed on the platform made of heat-resistant steel (reduced tank material or 310S stainless steel with the existing process) fixed by the bracket, and there is a gap between the material basket and the insulation layer, which is convenient for loading and unloading.

6. The power supply device applies power to the excitation coil, the power supply voltage is high, and the current of the feeding electrode is small. At the same time, the feed electrode is not in contact with the heating body, so there is no need to use water-cooled electrodes, the structure of the furnace body is simple, and the heat loss is small.

7. Due to the use of a separate coarse suction port, and the coarse suction port is located at the bottom of the furnace body, the dust in the furnace gas will not be deposited in the condenser, so the purity of crystalline magnesium is high.

8. The excitation coil is made of molybdenum or pure iron, a heat-resistant metal with low resistivity, because it has a high melting point and is resistant to oxidation; the conductor cross section of the excitation coil is set to be rectangular because the relative surface area of the conductor cross section is rectangular, and it is double Strands can improve heat transfer efficiency.

9. A scheme for embedding the excitation coil in the material basket is that there is a single spiral groove on the outer wall of the material basket, and the excitation coil is arranged in the groove. The space between the groove and the excitation coil is filled with high thermal conductivity ceramic insulating material, and a Thin metal baffle, with several air holes on the metal baffle, which effectively reduces the relaxation of the ceramic material and the basket wall due to the inconsistency of the expansion rates of the metal material and the ceramic material when the temperature changes, thereby affecting For heat transfer efficiency, the upper and lower sides of the metal baffle are folded respectively, and a steel strip is placed close to the folded edge. The two sides of the steel strip are welded to the wall of the basket by welding to form a closed current path, which can reduce the leakage inductance.

10. The charging or unloading of the reduction furnace is realized by removing the lower furnace cover as a whole. The feeding is directly added to the material basket, and the unloading is directly dumped into the material basket. The loading and unloading method of the reduction furnace is very convenient and fast.

The utility model has a reasonable design, can adjust the distribution of the temperature field of the reduction furnace, and has fast heat transfer efficiency; it is mainly used for the production of magnesium, lithium, strontium, calcium and other high-vapor-pressure metal thermal reduction methods.

Description of drawings

Fig. 1 is the overall structure sectional schematic diagram of the present utility model;

Fig. 2 is a distribution diagram of the material basket in the furnace body;

Fig. 3 is the schematic cross-sectional view of the wall groove of the feed basket;

Fig. 4 is a schematic diagram of the arrangement of local slits on the surface of the basket.

Detailed ways

Specific embodiments of the present utility model will be described in detail below in conjunction with the accompanying drawings.

As shown in Figures 1-4, a double-helix embedded excitation type electromagnetic induction internal heat magnesium vacuum reduction furnace in this embodiment includes an upper furnace shell 7, a lower furnace cover 1, a material basket 5, a platform 13, and a support frame 14 , a crystallization chamber 11 and a water cooling jacket 12, the basket 5 is composed of a basket 501, an excitation coil 502, a metal baffle 503 and a steel strip 504, the basket 501 is made of heat-resistant steel, and the basket 501 The outer wall is provided with a single helical groove 505, and the outer wall of the casing 501 is provided with a single helical magnesium steam overflow seam 509, which is arranged parallel to the groove 505, and the excitation coil 502 is arranged in the groove 505, and the conductor cross section of the excitation coil 502 is Rectangular, and double-helical coils are wound. The excitation coil enters from the bottom of the basket wall, spirals up, and is drawn out from the top. A ceramic material layer 506 is provided between the excitation coil 502 and the wall of the groove 505, and a metal baffle 503 is provided. Outside the groove 505, a number of air holes 507 are opened on the metal baffle 503, and the upper and lower sides of the metal baffle 503 are hemmed outwards, and the steel belt 504 is set close to the outside of the hemming, and the upper and lower sides of the steel belt 504 are It is welded on the wall of the basket 501, and the pelletized reducing charge 4 is filled in the material basket 5 and directly contacts with the wall of the material basket. The upper furnace shell 7 is closed on the lower furnace cover 1 to form a furnace body, and its sealing is guaranteed. The furnace body is made of ordinary carbon steel. The platform 13 is horizontally arranged at the bottom of the furnace body, and is supported and fixed by a support frame 14. Seven material baskets 5 are arranged on the platform 13 in a honeycomb shape, and are located in the furnace body, and the excitation coils 502 of the seven material baskets 5 are connected in parallel and then led out of the furnace through the insulating sealing device on the furnace body to connect with the power supply device. The top of the body is connected to the crystallization chamber 11 through the metal vapor channel 9, a fine pumping port 10 is provided on the upper part of the crystallization chamber 11, and a rough pumping port 3 is provided at the bottom of the furnace body, and the crystallization chamber 11 is respectively located on both sides of the furnace body, and the water cooling jacket 12 Set on the outer wall of the crystallization chamber 11. An insulating layer 8 is provided on the inner wall of the furnace body and the metal vapor channel 9 , and a gap 2 is left between the furnace body and the material basket 5 .

The above embodiments are only used to illustrate the technical solutions of the present utility model without limitation. Although detailed descriptions have been made with reference to the embodiments of the present utility model, those of ordinary skill in the art should understand that the technical solutions of the present utility model are modified or equivalently replaced. Neither deviate from the spirit and scope of the technical solutions of the present utility model, and all of them shall be covered by the protection scope of the claims of the present utility model.

Claims (4)

1. a kind of double helix embeds hot magnesium vacuum reduction stove in Exciting-simulator system electromagnetic induction, it is characterised in that：Including upper furnace shell (7), Lower bell (1), charging basket (5), platform (13), supporting rack (14), crystallisation chamber (11) and cooling device (12), the charging basket (5) by Basket (501), excitation coil (502), metal baffle (503) and steel band (504) composition, are opened in the outer wall of the basket (501) Equipped with a single helical groove (505), offers a single-screw magnesium steam overflow in the outer wall of basket (501) and stitch (509), and with Slot (505) is arranged in parallel, and excitation coil (502) is located in slot (505), and the cross-sectional area of conductor of excitation coil (502) is rectangle, and is Double-spiral coil is simultaneously entwined, and is introduced by charging basket (5) wall bottom, spiral, by Base top contact；In excitation coil (502) Insulating layer (506) is equipped between slot (505) wall, metal baffle (503) is located at slot (505) outside, and in metal baffle (503) Several stomatas (507) are offered, and makes metal baffle (503) both sides carries out flanging outward up and down, steel band (504) is close to roll over Setting on the outside of side, and make steel band (504) both sides are welded on the wall of basket (501) up and down, upper furnace shell (7) lid is closed in lower stove Furnace body is formed on lid (1), platform (13) is horizontally set on bottom of furnace body, and supports and fix by supporting rack (14), several charging baskets (5) it is arranged on platform (13) in honeycomb like, and in the furnace body, and after keeping the excitation coil (502) of several charging baskets (5) in parallel It leads to outside stove through the insulation seal device on furnace body and is connected with supply unit, at the top of furnace body even by metallic vapour channel (9) Connect crystallisation chamber (11), being equipped with essence on crystallisation chamber (11) top takes out mouth (10), bottom of furnace body be equipped with it is thick take out mouth (3), and with crystallization Room (11) is located at furnace body both sides, and cooling device (12) is located at the outer wall of crystallisation chamber (11).

2. a kind of double helix according to claim 1 embeds hot magnesium vacuum reduction stove in Exciting-simulator system electromagnetic induction, feature It is：Inner wall in the furnace body and metallic vapour channel (9) is equipped with insulating layer (8), and there are gaps between charging basket (5) (2)。

3. a kind of double helix according to claim 2 embeds hot magnesium vacuum reduction stove in Exciting-simulator system electromagnetic induction, feature It is：The insulating layer (506) is ceramic material layer.

4. embedding hot magnesium vacuum reduction in Exciting-simulator system electromagnetic induction according to a kind of double helix of claim 1-3 any one of them Stove, it is characterised in that：The cooling device (12) is water-cooled jacket.