阅读说明：本技术 一种用于高纯镁的真空气氛熔化炉及其熔化工艺 (Vacuum atmosphere melting furnace for high-purity magnesium and melting process thereof ) 是由 周森安 安俊超 李豪 郑传涛 于 2020-07-23 设计创作，主要内容包括：一种用于高纯镁的真空气氛熔化炉,包括控制机构、支撑架体和立式双层壳体,立式双层壳体的内部设置有主加热组件,顶部开设有进料口,在进料口处设有挡热阀,立式双层壳体的顶部还开设有真空组件连接口、惰性气体入口、添加剂入口和出料口,其中,真空组件连接口与外设的抽真空组件连接,惰性气体入口与外设的惰性气体气源连接,在立式双层壳体上还设有用于对其内部物料进行搅拌的内部多环搅拌组件。本发明通过对常规熔化炉结构和熔化工艺的改进,在相对较低的熔化温度和气氛保护条件下,实现对镁晶体节能、高效、高自动化程度和安全可靠性的熔化生产,以制备出高纯度的金属镁液体进行后续熔炼。(The utility model provides a vacuum atmosphere melting furnace for high-purity magnesium, which comprises a control mechanism, support body and vertical double shell, vertical double shell's inside is provided with main heating element, the feed inlet has been seted up at the top, be equipped with the heat retaining valve in feed inlet department, the vacuum module connector has still been seted up at vertical double shell's top, the inert gas entry, additive entry and discharge gate, wherein, the vacuum module connector is connected with the evacuation subassembly of peripheral hardware, the inert gas entry is connected with the inert gas air supply of peripheral hardware, still be equipped with the inside polycyclic stirring subassembly that is used for carrying out the stirring to its inside material on vertical double shell. The invention realizes the melting production of energy-saving, high-efficiency, high-automation degree and safe reliability of magnesium crystals under the relatively lower melting temperature and atmosphere protection condition by improving the structure and the melting process of the conventional melting furnace so as to prepare the high-purity magnesium metal liquid for subsequent melting.)

1. The utility model provides a vacuum atmosphere melting furnace for high-purity magnesium, includes control mechanism, supports support body (1) and sets up the vertical double shell body in support body (1) top, the inside of vertical double shell body is provided with main heating element, and this vertical double shell body includes interior casing (2) and shell body (3), around being equipped with resistance wire (4) that are used for carrying out auxiliary heating on the lateral wall surface of interior casing (2), still packs between interior casing (2) and shell body (3) insulation material (5), main heating element and resistance wire (4) all be connected its characterized in that with control mechanism: the top of a vertical double-layer shell is provided with a feed inlet (6), the feed inlet (6) is butted with a discharge port of a process upstream vacuum receiver (7), the feed inlet (6) of the vertical double-layer shell and the discharge port of the vacuum receiver (7) are both provided with a vacuum valve (8) for controlling the on-off of the feed inlet, a heat blocking valve (9) is arranged at the position of the feed inlet (6) below the vacuum valve (8), the top of the vertical double-layer shell is also provided with a vacuum component connecting port (10), an inert gas inlet (11), an additive inlet (12) and a discharge port, wherein the vacuum component connecting port (10) is connected with an external vacuumizing component (13), the inert gas inlet (11) is connected with an external inert gas source (14), the discharge port is provided with a discharge pipe (15), one end of the discharge pipe (15) is arranged below the liquid level of the metal liquid in the vertical double-layer, the other end of the discharge pipe (15) is in butt joint with a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process, an electric control valve (16) and a metering pump (17) are further arranged on the discharge pipe (15), an internal multi-ring stirring assembly for stirring the internal materials is further arranged on the vertical double-layer shell, and the vacuum valve (8), the heat blocking valve (9), the vacuumizing assembly (13), the inert gas source (14), the electric control valve (16), the metering pump (17) and the internal multi-ring stirring assembly are all connected with a control mechanism.

2. A vacuum atmosphere melting furnace for high purity magnesium according to claim 1, wherein: the feed inlet (6) is arranged at the center of the top of the vertical double-layer shell.

3. A vacuum atmosphere melting furnace for high purity magnesium according to claim 1, wherein: the discharge port is arranged on one side inside the vertical double-layer shell.

4. A vacuum atmosphere melting furnace for high purity magnesium according to claim 1, wherein: the main heating assembly comprises a plurality of furnace heating pipes (18) which are vertically arranged in an inner shell (2), the lower ends of the furnace heating pipes (18) extend out of the inner bottom surface of the inner shell (2) to the outer shell (3) and are of an open structure, a heating element (19) which is in an inverted U shape is arranged inside each furnace heating pipe (18), a supporting cover (20) is further arranged below each furnace heating pipe (18), and a clamping device used for fixing the heating element (19) is arranged on each supporting cover (20).

5. A vacuum atmosphere melting furnace for high purity magnesium according to claim 4, characterized in that: the heating pipes (18) in the furnace are vertically welded on the lower bottom surface of the inner shell (2), and the heating pipes (18) in the furnace are uniformly arranged in the inner shell (2).

6. A vacuum atmosphere melting furnace for high purity magnesium according to claim 1 or 4, characterized in that: the internal multi-ring stirring component consists of a driving motor (21) and a multi-ring stirrer, the driving motor (21) is arranged at the top of the vertical double-layer shell and is connected with a control mechanism, the multi-ring stirrer is arranged inside the vertical double-layer shell and comprises a plurality of horizontal ring groups and a stirring shaft (22) which are arranged in parallel from top to bottom, each horizontal ring group comprises a plurality of concentric rings (23), the concentric rings (23) are arranged by avoiding a main heating component in the vertical double-layer shell, a vertical fixing rod (24) is connected between the upper concentric rings (23) and the lower concentric rings in parallel from top to bottom, the upper end of the stirring shaft (22) extends out of the vertical double-layer shell to be connected with an output shaft of the driving motor (21), the lower end of the stirring shaft (22) is connected to one horizontal ring group which is positioned at the top, and a plurality of horizontal fixing rods (25) are radially arranged on the horizontal ring group which is positioned, and a plurality of horizontal fixing rods (25) are welded on the stirring shaft (22).

7. A vacuum atmosphere melting furnace for high purity magnesium according to claim 6, characterized in that: the horizontal plane of the horizontal ring group positioned at the top in the vertical double-layer shell is higher than the horizontal plane of the top end of the main heating assembly.

8. A vacuum atmosphere melting furnace for high purity magnesium according to claim 6, characterized in that: the horizontal fixing rods (25) are of an integral structure, and the horizontal fixing rods (25) are uniformly arranged along the circumferential direction of a circle where the horizontal fixing rods are located.

9. The process for melting metallic magnesium using a vacuum atmosphere melting furnace for high purity magnesium according to claim 1, comprising the steps of:

a. the vacuum valve (8) and the heat-blocking valve (9) at the feed inlet (6) of the vertical double-layer shell are regulated and controlled to be closed by the control mechanism, and an external vacuumizing assembly (13) is controlled to vacuumize the interior of the vertical double-layer shell through a vacuum assembly connecting port (10);

b. the vacuum valve (8) at the discharge port of the upstream vacuum receiver (7) of the process, the vacuum valve (8) at the feed port (6) of the vertical double-layer shell and the heat blocking valve (9) are controlled by a control mechanism to be opened, so that the high-purity metal magnesium crystals in the vacuum receiver (7) automatically fall into the vertical double-layer shell;

c. a control mechanism is used for regulating and controlling the vacuum valve (8) at the discharge port of a process upstream vacuum receiver (7), the vacuum valve (8) and the heat-blocking valve (9) at the feed port (6) of the vertical double-layer shell to be closed, and regulating and controlling an external inert gas source (14) to fill inert gas into the vertical double-layer shell through an inert gas inlet (11) until the pressure in the vertical double-layer shell is 0.1 MPa;

d. the main heating component and the resistance wire (4) are regulated and controlled by the control mechanism to heat the materials in the vertical double-layer shell, so that the temperature in the vertical double-layer shell is raised to 700-;

e. regulating and controlling an internal multi-ring stirring component by a control mechanism to stir the materials for 3-5 min;

f. the control mechanism regulates and controls the electric control valve (16) and the metering pump (17), liquid magnesium samples are extracted from the vertical double-layer shell for assay, whether the magnesium samples meet the requirement of high-purity magnesium or not is detected, if the magnesium samples meet the requirement, the electric control valve (16) and the metering pump (17) are controlled to be opened, and magnesium liquid is extracted through the discharge pipe (15) to a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process for subsequent treatment;

g. if the magnesium liquid does not meet the requirement, proper additives are added into the vertical double-layer shell through the additive inlet (12) and the internal multi-ring stirring component is regulated and controlled to stir the materials, so that the additives react with the overproof elements and are precipitated at the bottom of the furnace, the internal multi-ring stirring component is regulated and controlled to be closed, the materials in the vertical double-layer shell are kept standing for 5-10min, then the electric control valve (16) and the metering pump (17) are regulated and controlled to be opened through the control mechanism, and the magnesium liquid is pumped out through the discharge pipe (15) to a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process for subsequent treatment.

Technical Field

The invention relates to the technical field of industrial magnesium purification equipment, in particular to a vacuum atmosphere melting furnace for high-purity magnesium and a melting process thereof.

Background

The magnesium alloy is a high-performance light structural material taking magnesium as a raw material, has the specific gravity similar to that of plastic, has the rigidity and the strength not inferior to those of aluminum, has the excellent performances of stronger shock resistance, electromagnetic resistance, heat conduction, electric conduction and the like, and can be completely recycled without pollution. The magnesium alloy has light weight, the density of the magnesium alloy is only 1.7 kg/m3, the magnesium alloy is 2/3 of aluminum, the strength of the magnesium alloy is 1/4 of steel, the magnesium alloy is higher than that of the aluminum alloy and the steel, the specific stiffness of the magnesium alloy is close to that of the aluminum alloy and the steel, the magnesium alloy can bear certain load, the magnesium alloy has good castability and dimensional stability, is easy to process, has low rejection rate and good damping coefficient, has larger damping capacity than the aluminum alloy and the cast iron, is very suitable for the production of automobiles, and has wide application space in the fields of aerospace, portable computers, mobile phones, electrical appliances, sports equipment and the like.

The main defects of the common magnesium alloy are poor corrosion resistance, the function of the magnesium alloy is easy to lose effectiveness in a short time due to corrosion in certain environments, the impurity harmful elements mainly comprise Fe, Ni, Cu, Be, Si, Sr, Sb, Sn and the like, and the existence of the trace elements directly influences the performance and the service life of the magnesium alloy.

The magnesium metal is a matrix of magnesium alloy, the magnesium content in the national standard magnesium metal is 99.92-99.98%, but the national standard measurement method is to measure the content of partial impurities only, the content of the elements of the partial impurities mainly used for measurement is 0.0001-0.02%, the content of several measured impurities is subtracted from the total amount of the alloy, and the magnesium content is remained as default. In fact, the actual magnesium content of standard industrial magnesium is less than 99.9% due to the high level of harmful impurities in the magnesium metal. The magnesium alloy containing harmful impurities is obviously inferior to the magnesium alloy prepared by high-purity magnesium metal in various properties, namely: in the preparation process of the magnesium alloy, how to prepare high-purity metal magnesium with higher purity and then quantitatively add other alloy elements directly influences the quality and performance of the finished magnesium alloy.

At present, the containers for smelting magnesium metal in the prior art mainly comprise low-carbon steel crucibles and stainless steel containers, and the apparatuses generally have the following remarkable defects when smelting or melting high-purity magnesium metal: 1. because the existing melting equipment only heats outside the equipment, the heat conduction efficiency is low, the heat loss is large, and the low-carbon steel crucible and the stainless steel container have poor self corrosion resistance at high temperature, so that impurities are easily generated in the container to pollute magnesium metal; 2. the melting process of magnesium metal is usually carried out in air, and metal magnesium at high temperature is active due to chemical properties and is easy to oxidize, in order to prevent the metal magnesium from oxidizing, a covering agent and nitrogen are required to be added, and the covering agent can cause secondary pollution; 3. the existing melting equipment has low melting efficiency, so that the preparation process period is long, the equipment is usually large in size, and the safety cannot be guaranteed.

Therefore, how to prepare a vacuum atmosphere melting furnace which can avoid the oxidation or secondary pollution of the magnesium metal in the melting process of the magnesium crystal, can effectively regulate and control the impurity content in the magnesium metal in the furnace, has high automation degree and good safety is necessary for producing high-purity magnesium.

Disclosure of Invention

The technical purpose of the invention is as follows: through the improvement of the structure and the melting process of the conventional melting furnace, the energy-saving, high-efficiency, high-automation-degree and safe and reliable melting production of magnesium crystals is realized under the relatively low melting temperature and atmosphere protection condition, so that the high-purity magnesium metal liquid is prepared for subsequent melting.

The technical scheme adopted by the invention for solving the technical problems is as follows: a vacuum atmosphere melting furnace for high-purity magnesium comprises a control mechanism, a supporting frame body and a vertical double-layer shell arranged above the supporting frame body, wherein a main heating assembly is arranged inside the vertical double-layer shell, the vertical double-layer shell comprises an inner shell and an outer shell, a resistance wire for auxiliary heating is wound on the outer surface of the side wall of the inner shell, a heat insulation material is filled between the inner shell and the outer shell, the main heating assembly and the resistance wire are both connected with the control mechanism, a feed inlet is formed in the top of the vertical double-layer shell and is in butt joint with a discharge opening of a process upstream vacuum receiver, vacuum valves for controlling the on-off of the feed inlet of the vertical double-layer shell and the discharge opening of the vacuum receiver are arranged at the feed inlet, a heat blocking valve is further arranged at the position below the vacuum valves, and a vacuum assembly connecting port is further formed in the top of, The device comprises an inert gas inlet, an additive inlet and a discharge port, wherein a vacuum component connecting port is connected with an external vacuumizing component, the inert gas inlet is connected with an external inert gas source, a discharge pipe is arranged at the discharge port, one end of the discharge pipe is arranged below the liquid level of the metal liquid in the vertical double-layer shell, the other end of the discharge pipe is in butt joint with a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process, an electric control valve and a metering pump are further arranged on the discharge pipe, an internal multi-ring stirring component for stirring the materials in the vertical double-layer shell is further arranged on the vertical double-layer shell, and the vacuum valve, the heat blocking valve, the vacuumizing component, the inert gas source, the electric control valve, the metering pump and the internal multi.

Preferably, the feed inlet is arranged at the center of the top of the vertical double-layer shell.

Preferably, the discharge port is arranged on one side of the interior of the vertical double-layer shell.

Preferably, the main heating assembly comprises a plurality of furnace heating pipes vertically arranged in the inner shell, the lower ends of the furnace heating pipes extend out of the inner bottom surface of the inner shell to the outer shell and are of an open structure, a heating element in an inverted U shape is arranged in each furnace heating pipe in a matched mode, a supporting cover is further arranged below each furnace heating pipe, and a clamping device used for fixing the heating element is arranged on each supporting cover.

Preferably, the furnace heating pipes are vertically welded on the lower bottom surface of the inner shell, and the plurality of furnace heating pipes are uniformly arranged in the inner shell.

Preferably, the internal multi-ring stirring assembly consists of a driving motor and a multi-ring stirrer, the driving motor is arranged at the top of the vertical double-layer shell and is connected with the control mechanism, the multi-ring stirrer is arranged inside the vertical double-layer shell, the multi-ring stirrer comprises a plurality of horizontal ring groups and a stirring shaft which are arranged in parallel up and down, each horizontal ring group comprises a plurality of concentric rings, the concentric rings are arranged to avoid a main heating component in a vertical double-layer shell, a vertical fixed rod is connected between the concentric rings which are parallel up and down, the upper end of the stirring shaft extends out of the vertical double-layer shell to be connected with the output shaft of the driving motor, the lower end of the stirring shaft is connected with the horizontal ring group which is positioned at the top, the horizontal ring group positioned at the top is also radially provided with a plurality of horizontal fixing rods, and the horizontal fixing rods are all welded on the stirring shaft.

Preferably, the horizontal plane of the horizontal ring group positioned at the uppermost part in the vertical double-layer shell is higher than the horizontal plane of the top end of the main heating assembly.

Preferably, the plurality of horizontal fixing rods are of an integral structure, and the plurality of horizontal fixing rods are uniformly arranged along the circumferential direction of a circle where the plurality of horizontal fixing rods are located.

A melting process for a vacuum atmosphere melting furnace for high purity magnesium, comprising the steps of:

a. the control mechanism regulates and controls the vacuum valve and the heat-blocking valve at the feed inlet of the vertical double-layer shell to be closed, and controls an external vacuumizing assembly to vacuumize the interior of the vertical double-layer shell through a vacuum assembly connecting port;

b. the vacuum valve at the discharge port of the upstream vacuum receiver of the process, the vacuum valve at the feed port of the vertical double-layer shell and the heat-blocking valve are controlled to be opened by a control mechanism, so that the high-purity magnesium metal crystals in the vacuum receiver automatically fall into the vertical double-layer shell;

c. the vacuum valve at the discharge port of the process upstream vacuum receiver and the vacuum valve and the heat-blocking valve at the feed port of the vertical double-layer shell are regulated and controlled to be closed by a control mechanism, and an external inert gas source is regulated and controlled to fill inert gas into the vertical double-layer shell through an inert gas inlet until the pressure in the vertical double-layer shell is 0.1 MPa;

d. the main heating component and the resistance wire are regulated and controlled by the control mechanism to heat the materials in the vertical double-layer shell, so that the temperature in the vertical double-layer shell is raised to 700-;

e. regulating and controlling an internal multi-ring stirring component by a control mechanism to stir the materials for 3-5 min;

f. regulating and controlling the electric control valve and the metering pump through the control mechanism, extracting a liquid magnesium sample from the vertical double-layer shell for assay, detecting whether the magnesium sample meets the requirement of high-purity magnesium, and if the magnesium sample meets the requirement, controlling the electric control valve and the metering pump to be opened, and extracting magnesium liquid through the discharge pipe to a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process for subsequent treatment;

g. if the magnesium liquid does not meet the requirement, proper additives are added into the vertical double-layer shell through the additive inlet under the regulation and control of the control mechanism, the internal multi-ring stirring component is regulated and controlled to stir the materials, the additives react with the overproof elements and are precipitated at the bottom of the furnace, the internal multi-ring stirring component is regulated and controlled to be closed, the materials in the vertical double-layer shell are kept standing for 5-10min, then the electric control valve and the metering pump are controlled to be opened under the regulation and control of the control mechanism, and the magnesium liquid is pumped out through the discharge pipe to a vacuum magnesium alloy smelting furnace or a forming mold.

The invention has the beneficial effects that:

1. according to the vacuum atmosphere melting furnace for high-purity magnesium, the main heating assembly and the auxiliary heating resistance wire with material heating functions are respectively arranged inside and outside the inner shell, so that the materials in the furnace body are efficiently and quickly heated. The whole heating process is high in heat transfer efficiency and heating efficiency, small in heat loss and remarkable in energy-saving effect, the production cost of the melting process is reduced, and more importantly, due to the fact that the heat transfer efficiency of the whole furnace body is high, the inside and the outside of the furnace body do not need to bear high temperature which is greatly higher than the melting temperature in order to reach the melting temperature of internal materials, corrosion of the furnace body under the high-temperature condition and pollution to metal magnesium crystals are avoided, and high purity of the magnesium crystals in the melting process is guaranteed.

2. According to the vacuum atmosphere melting furnace for high-purity magnesium, provided by the invention, through the arrangement of the structures such as the additive inlet, the discharging pipe, the metering pump, the electric control valve and the like in the device, the impurity content of the metal magnesium liquid in the furnace body can be detected and regulated in the melting process of crystal magnesium, so that the impurity content meets the purity requirement of the subsequent process, and the vacuum atmosphere melting furnace for high-purity magnesium has the advantages of strong operability and good safety and reliability.

3. According to the vacuum atmosphere melting furnace for high-purity magnesium, the internal multi-ring stirring assembly with a unique structure is arranged, metal materials in the furnace can be well homogenized in the process of melting crystal magnesium, the uniformity of the quality of finished metal magnesium can be guaranteed, the additives can be fully contacted and reacted with impurities in the metal magnesium after being added, the precipitation of reaction products is facilitated, and the purity of molten finished metal magnesium liquid is greatly improved to a certain extent.

4. The melting process has the advantages of simple steps, convenient operation and control and high automation degree, and the operation steps of firstly vacuumizing the melting furnace and then protecting the melting furnace by inert gas atmosphere not only ensure that the whole melting process can avoid the magnesium metal from being oxidized or polluted by impurities, but also realize the pollution-free better butt joint of the melting furnace and the whole upstream and downstream equipment, thereby fundamentally ensuring the purity of the finished magnesium metal.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic cross-sectional view of the interior of the vertical double shell of the present invention;

FIG. 3 is a schematic view of a multi-ring agitator;

reference numerals: 1. support the support body, 2, interior casing, 3, the shell body, 4, the resistance wire, 5, insulation material, 6, the feed inlet, 7, vacuum receiver, 8, the vacuum valve, 9, keep off the hot valve, 10, the vacuum module connector, 11, the inert gas entry, 12, the additive entry, 13, the evacuation subassembly, 14, the inert gas air supply, 15, the discharging pipe, 16, automatically controlled valve, 17, the measuring pump, 18, the interior heating pipe of stove, 19, heating element, 20, support the lid, 21, driving motor, 22, (mixing) shaft, 23, concentric ring, 24, vertical fixing rod, 25, horizontal fixing rod.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings:

as shown in the figure, the vacuum atmosphere melting furnace for high-purity magnesium comprises a control mechanism, a support frame body 1 and a vertical double-layer shell arranged above the support frame body 1, wherein a main heating assembly is arranged inside the vertical double-layer shell, the vertical double-layer shell comprises an inner shell 2 and an outer shell 3, a resistance wire 4 for auxiliary heating is wound on the outer surface of the side wall of the inner shell 2, a heat insulation material 5 is filled between the inner shell 2 and the outer shell 3, the main heating assembly and the resistance wire 4 are both connected with the control mechanism, a feed inlet 6 is formed in the top of the vertical double-layer shell, the feed inlet 6 is formed in the center of the top of the vertical double-layer shell, the feed inlet 6 is in butt joint with a discharge port of a process upstream vacuum receiver 7, and a vacuum valve 8 for controlling the on-off of the feed inlet 6 of the vertical double-layer shell and the discharge, a heat retaining valve 9 is further arranged at the position, below the vacuum valve 8, of the feed inlet 6, a vacuum component connecting port 10, an inert gas inlet 11, an additive inlet 12 and a discharge port are further formed in the top of the vertical double-layer shell, wherein the vacuum component connecting port 10 is connected with an external vacuumizing component 13, the inert gas inlet 11 is connected with an external inert gas source 14, the discharge port is formed in one side of the interior of the vertical double-layer shell, a discharge pipe 15 is arranged at the discharge port, one end of the discharge pipe 15 is arranged below the liquid level of the metal liquid in the interior of the vertical double-layer shell, the other end of the discharge pipe 15 is in butt joint with a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process, an electric control valve 16 and a metering pump 17 are further arranged on the discharge pipe 15, and an internal multi-, the vacuum valve 8, the heat blocking valve 9, the vacuumizing assembly 13, the inert gas source 14, the electric control valve 16, the metering pump 17 and the internal multi-ring stirring assembly are all connected with the control mechanism.

The main heating assembly comprises a plurality of furnace heating pipes 18 which are vertically arranged inside the inner shell 2, the lower ends of the furnace heating pipes 18 extend out of the inner bottom surface of the inner shell 2 to the outer shell 3 and are of an open structure, the furnace heating pipes 18 are vertically welded on the lower bottom surface of the inner shell 2, and the furnace heating pipes 18 are uniformly arranged inside the inner shell 2, as shown in the attached drawing 2. An inverted U-shaped heating element 19 is arranged inside each heating tube 18 in the furnace, a supporting cover 20 is arranged below each heating tube 18 in the furnace, and a clamping device for fixing the heating element 19 is arranged on the supporting cover 20.

Preferably, the internal multi-ring stirring assembly comprises a driving motor 21 and a multi-ring stirrer, the driving motor 21 is arranged at the top of the vertical double-layer shell and is connected with the control mechanism, the multi-ring stirrer is arranged inside the vertical double-layer shell and comprises a plurality of horizontal ring groups and a stirring shaft 22 which are arranged in parallel from top to bottom, each horizontal ring group comprises a plurality of concentric rings 23, the concentric rings 23 are arranged to avoid the main heating assembly in the vertical double-layer shell, a vertical fixing rod 24 is connected between the upper and lower parallel concentric rings 23, the upper end of the stirring shaft 22 extends out of the vertical double-layer shell and is connected with an output shaft of the driving motor 21, the lower end of the stirring shaft 22 is connected to the horizontal ring group at the top, and a plurality of horizontal fixing rods 25 are radially arranged on the horizontal ring group at the top, a plurality of horizontal fixing pole 25 structure as an organic whole, and a plurality of horizontal fixing pole 25 evenly set up along the circumference of its place circle, and a plurality of horizontal fixing pole 25 all weld on (mixing) shaft 22, the horizontal plane that the horizontal ring group that is located the top in the vertical double shell is located is higher than the horizontal plane that main heating element top was located.

When the heating pipe in the furnace of the vacuum atmosphere melting furnace for high-purity magnesium is damaged, the following method can be adopted for corresponding maintenance. Firstly, the clamping device on the supporting cover is taken down, then the mounting flange (namely the supporting cover) at the bottom of the heating pipe in the furnace is opened, and at the moment, the damaged heating element can be taken out from the heating pipe in the furnace for corresponding replacement and maintenance. After the overhaul is finished, the mounting flange at the bottom of the heating pipe in the furnace is fixed in sequence, and the bottom end of the heating element (U-shaped silicon carbide rod) is fixed on the mounting flange through a clamping device.

The components in the vertical double-layer shell are all made of stainless steel, the heating tube is also made of stainless steel, the upper part of the stainless steel tube is a blind head, the lower part of the stainless steel tube is welded with the bottom of the vacuum furnace body, the U-shaped silicon carbide rod heating element is inserted into the furnace from bottom to top, and the cold end of the heating element is provided with a baffle plate in a supporting cover shape.

The invention discloses a vacuum atmosphere melting furnace for high-purity magnesium, which is characterized in that: 1. the metal magnesium crystals collected by the vacuum receiver can automatically fall into the stainless steel vertical double-layer shell by opening the two vacuum valves at the upper part of the vertical double-layer shell; 2. before the vacuum atmosphere melting furnace is heated, the vacuum valve connected with the vacuum receiver at the upper part of the furnace body is closed, inert gas is introduced, and then high-purity magnesium is heated and melted, so that the volatilization of magnesium vapor is reduced, unnecessary loss is reduced, and the oxidation of high-purity metal magnesium is avoided; 3. the two vacuum valves on the top of the vertical double-layer shell are closed, so that inert gas can be prevented from entering the vacuum receiver, and waste is caused; 4. the heat blocking valve at the top of the vertical double-layer shell is closed, so that not only can the loss of heat in the furnace be avoided, but also the heat in the furnace can be prevented from entering a vacuum receiver at the upstream of the process, magnesium crystals in the vacuum receiver are melted, and adhesion is caused on the inner wall of the vacuum receiver; 5. after the magnesium crystal is melted, the magnesium liquid can be conveyed to a vacuum atmosphere mixing furnace subsequent to the process through a metering pump, and can also be directly conveyed to a magnesium product mold for molding; 6. the heating assembly is characterized by dual-system heating, namely, an in-furnace heating system formed by inserting a U-shaped heating element into a furnace tube is taken as a main part, and electric furnace wires arranged on the inner surface of a heat insulation material at the periphery of a furnace tank are taken as an auxiliary part to carry out synergistic heating. The mode that the heating furnace tube is inserted into the furnace tank to heat the material is adopted, the heat emitted by the heating body is directly transferred to the material through the furnace tube, the heat efficiency is improved, and the energy conservation is realized; 7. the internal heating method that the heating pipe is inserted into the furnace body is beneficial to improving the heating efficiency, realizing energy conservation, shortening the processing process period and reducing the production cost of the melting process, and simultaneously, the heat transfer efficiency is high, so that the inside and the outside of the furnace body do not need to bear the high temperature which is greatly higher than the melting temperature in order to reach the melting temperature of the internal materials, thereby avoiding the corrosion of the furnace body under the high temperature condition and the pollution to the metal magnesium crystal, and further ensuring the high purity in the melting process of the magnesium crystal.

A melting process for a vacuum atmosphere melting furnace for high purity magnesium, comprising the steps of:

a. the control mechanism regulates and controls the vacuum valve 8 and the heat-blocking valve 9 at the feed inlet 6 of the vertical double-layer shell to be closed, and controls an external vacuumizing assembly 13 to vacuumize the interior of the vertical double-layer shell through a vacuum assembly connecting port 10;

b. the vacuum valve 8 at the discharge port of the upstream vacuum receiver 7 of the process, the vacuum valve 8 at the feed port 6 of the vertical double-layer shell and the heat-blocking valve 9 are controlled by a control mechanism to be opened, so that the high-purity magnesium metal crystals in the vacuum receiver 7 automatically fall into the vertical double-layer shell;

c. the vacuum valve 8 at the discharge port of the process upstream vacuum receiver 7, the vacuum valve 8 at the feed port 6 of the vertical double-layer shell and the heat-blocking valve 9 are regulated and controlled to be closed by the control mechanism, and the inert gas source 14 arranged outside is regulated and controlled to fill inert gas into the vertical double-layer shell through the inert gas inlet 11 until the pressure in the vertical double-layer shell is 0.1 MPa;

d. the main heating component and the resistance wire 4 are regulated and controlled by the control mechanism to heat the materials in the vertical double-layer shell, so that the temperature in the vertical double-layer shell is raised to 700-;

e. regulating and controlling an internal multi-ring stirring component by a control mechanism to stir the materials for 3-5 min;

f. the electric control valve 16 and the metering pump 17 are regulated and controlled by the control mechanism, a liquid magnesium sample is extracted from the vertical double-layer shell for assay, whether the magnesium sample meets the requirement of high-purity magnesium or not is detected, if the magnesium sample meets the requirement, the electric control valve 16 and the metering pump 17 are controlled to be opened, and magnesium liquid is extracted from the discharging pipe 15 to a vacuum magnesium alloy smelting furnace or a forming mold at the downstream of the process for subsequent treatment;

g. if the magnesium liquid does not meet the requirements, proper additives are added into the vertical double-layer shell through the additive inlet 12 and the internal multi-ring stirring component is regulated and controlled by the control mechanism to stir the materials, so that the additives react with the overproof elements and are precipitated at the bottom of the furnace, the internal multi-ring stirring component is regulated and controlled to be closed, the materials in the vertical double-layer shell are kept standing for 5-10min, then the electric control valve 16 and the metering pump 17 are regulated and controlled by the control mechanism to be opened, and the magnesium liquid is pumped out through the discharge pipe 15 to a vacuum magnesium alloy smelting furnace or a forming die at the downstream of the process.

The additive added in the process is a trace element additive, and the trace element additive is preheated before being added through an additive inlet, wherein the preheating temperature is 200 +/-20 ℃.

Various pumps and valves are electric control components, and can be automatically controlled through a plc type control mechanism.