CN111842844B - Rare earth metal vacuum suction casting device and method - Google Patents

Abstract

The invention discloses a rare earth metal vacuum suction casting device and a rare earth metal vacuum suction casting method, wherein the device comprises a cavity and further comprises the following steps: the suction casting pipe is inserted into the lower end of the cavity; one end of the vacuum tube is inserted into the upper end of the cavity, the other end is connected with the vacuum tank, the vacuum tube is provided with an extraction valve and a pressure relief valve; the electrolyte overflow box is communicated with the vacuum tube and used for collecting overflowed electrolyte, and a liquid level sensor is arranged at the lower end of the joint of the vacuum tube and the electrolyte overflow box and used for outputting a signal whether the liquid level reaches the joint; and the controller is in signal connection with the liquid level sensor, the extraction valve and the pressure relief valve and is used for receiving the signals and controlling the opening and closing of the extraction valve and the pressure relief valve. The invention adopts the vacuum device to suction cast and shape the liquid rare earth metal, avoids the oxidation of the rare earth metal in the air, does not need to wrap electrolyte, improves the purity of the rare earth metal, and realizes the control of the extraction valve and the pressure release valve through the liquid level signal by connecting the controller with the liquid level sensor and the extraction valve and the pressure release valve through signals.

Description

A rare earth metal vacuum suction casting device and method

Technical Field

The invention relates to the technical field of rare earth processing, and in particular to a rare earth metal vacuum suction casting device and method.

Background Art

Rare earth metals, also known as rare earth elements, are a general term for 17 elements in the scandium, yttrium, and lanthanide series in the IIIB group of the periodic table, usually represented by R or RE. Rare earth metals are highly chemically active and when reacting with oxygen, they generate highly stable _{R2O3 -} type oxides.

The existing rare earth metal casting method uses a method of adding electrolytes into the liquid rare earth metal to improve the stability of the rare earth metal and cast it. For example, Chinese invention patent CN106799487A discloses an automatic tipping system for rare earth metal casting and molding machinery, including a base and a clamping device for clamping a pot body. The base is provided with a tipping drive device, which is connected to the clamping device and can drive the clamping device to tip sideways. However, this casting method has the following disadvantages: a large amount of electrolyte is mixed in the rare earth metal after casting, which makes the purity of the rare earth metal low.

In view of this, there is an urgent need to improve the existing rare earth metal casting device to increase the purity of the rare earth metal.

Summary of the invention

The invention discloses a rare earth metal vacuum suction casting device and method, which are used to solve the problem of low purity of extracted rare earth metals in the prior art.

In order to solve the above problems, the present invention adopts the following technical solutions:

A rare earth metal vacuum suction casting device is provided, comprising a mold cavity and further comprising:

A suction casting tube is inserted into the lower end of the cavity;

A vacuum tube, one end of which is plugged into the upper end of the cavity and the other end of which is connected to a vacuum tank, wherein the vacuum tube is provided with an air extraction valve for vacuuming and a pressure relief valve for pressure relief;

An electrolyte overflow box is connected to the vacuum tube and is used to collect overflowed electrolyte. A liquid level sensor is provided at the lower end of the connection between the vacuum tube and the electrolyte overflow box. The liquid level sensor is used to output a signal of whether the liquid level reaches that location.

A controller is connected to the liquid level sensor, the air extraction valve and the pressure relief valve signals, and is used to receive the signals and control the opening and closing of the air extraction valve and the pressure relief valve. The controller includes a timer and is configured to perform the following steps:

S1 controls the air extraction valve and the air release valve to close after receiving the signal indicating that the liquid level has reached;

S2: the timer starts timing, and when a signal indicating that the liquid level has not been reached is received within a preset time, the air extraction valve is controlled to open after the preset time has expired, and the process returns to S1, and when no signal indicating that the liquid level has not been reached is received within the preset time, the air release valve is controlled to open;

The mold cavity comprises a first mold cavity and a second mold cavity, and a plurality of one-to-one corresponding models are arranged inside the first mold cavity and the second mold cavity;

The inner sides of the first cavity and the second cavity are also provided with a direct current runner and a cross-flow runner, wherein the direct current runner is vertically arranged at the middle position of the inner sides of the first cavity and the second cavity, and the cross-flow runner is arranged downwardly at both sides of the direct current runner and is connected to each of the molds;

The upper and lower ends of the DC runner are respectively provided with a first riser and a second riser, the upper end of the first riser is connected to the vacuum tube through a first flange, and the lower end of the second riser is connected to the suction casting tube through a second flange;

The first riser and the second riser are fixed on the second cavity, and the first cavity is provided with a pouring mouth adapted to the first riser and the second riser;

A cylinder is disposed on the outer side of the first cavity. The first cavity and the second cavity are positioned around by sliding guide rods. The cylinder drives the second cavity to slide along the sliding guide rods.

In the above scheme, the cylinder is fixed on the lifting platform and is used to adjust the depth of the suction casting tube inserted into the rare earth electrolytic furnace.

In the above scheme, a sealing cover is provided at the upper end of the electrolyte overflow box, and an observation portion is provided on the sealing cover for observing the overflow of the liquid metal, and the observation portion is made of a transparent material.

In the above solution, a vacuum pressure gauge is also provided on the vacuum tube for detecting the pressure value.

In the above solution, there is a titanium coating in the cavity.

The suction casting method using the rare earth metal vacuum suction casting device comprises:

Insert the suction casting tube into the bottom of the metal receiver of the rare earth electrolysis furnace, and drive the second cavity to slide and buckle with the first cavity, so that the suction casting tube, the cavity, the first riser, the second riser, the vacuum tube, the electrolyte overflow box and the vacuum tank are sealed and connected;

Open the air extraction valve and close the pressure relief valve;

When receiving the signal that the liquid level has reached, the controller controls the air extraction valve and the air release valve to close;

The timer starts timing. When a signal indicating that the liquid level has not been reached is received within a preset time, the controller controls the air extraction valve to open after the preset time ends. When no signal indicating that the liquid level has not been reached is received within the preset time, the controller controls the air release valve to open to cool the liquid rare earth metal.

After the cavity is cooled, the cylinder drives the second cavity to slide to open the cavity and take out the rare earth metal.

In the above solution, the air extraction valve is an electromagnetic air extraction valve.

In the above scheme, after the pressure relief valve is opened and the air extraction valve is closed, the liquid in the vacuum tube and the suction casting tube flows back to the rare earth electrolysis furnace.

The technical solution adopted by the present invention can achieve the following beneficial effects:

A vacuum device is used to suction-cast the liquid rare earth metal to avoid oxidation of the rare earth metal during the casting process. The controller is connected to the liquid level sensor, the air extraction valve and the pressure relief valve signal, and the air extraction valve and the pressure relief valve are controlled by the liquid level signal. Risers are set at the upper and lower ends of the DC runner to prevent turbulence when the air is pumped. The device is used to suction-cast the liquid rare earth metal without electrolyte wrapping, thereby improving the purity of the rare earth metal.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

FIG1 is a schematic diagram of the overall structure of a rare earth metal vacuum suction casting device disclosed in Example 1 of the present invention;

FIG2 is a schematic structural diagram of a mold cavity of a rare earth metal vacuum suction casting device disclosed in Example 1 of the present invention;

FIG3 is a front view of the rare earth metal vacuum suction casting device disclosed in Example 1 of the present invention;

FIG4 is a flow chart of the rare earth metal vacuum suction casting method disclosed in Example 2 of the present invention.

Specifically include the following figure signs:

Cavity-10; suction casting tube 20; vacuum tube-30; cylinder-40; lifting platform-50; first cavity-11; second cavity-12; model-13; direct current runner-14; cross flow runner-15; sliding guide rod-16; vacuum tank-31; exhaust valve-32; pressure relief valve-33; electrolyte overflow box-34; vacuum pressure gauge-35; liquid level sensor-36; controller-37; pouring mouth-111; first riser-141; second riser-142; observation part-341.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

Example 1

As shown in FIGS. 1 to 3 , the rare earth metal vacuum suction casting device of the present invention includes a mold cavity 10 and further includes:

The suction casting tube 20 is plugged into the lower end of the cavity 10; the vacuum tube 30 is plugged into the upper end of the cavity 10 at one end and connected to the vacuum tank 31 at the other end. The vacuum tube 30 is provided with an exhaust valve 32 for vacuuming and a pressure relief valve 33 for pressure relief. The exhaust valve 32 may be an electromagnetic exhaust valve; the electrolyte overflow box 34 is connected to the vacuum tube 30 and is used to collect the overflowed electrolyte. A liquid level sensor 36 is provided at the lower end of the connection between the vacuum tube 30 and the electrolyte overflow box 34. The liquid level sensor 36 is used to output a signal indicating whether the liquid level has reached that place; the controller 37 is connected to the liquid level sensor 36, the exhaust valve 32 and the pressure relief valve 33 for receiving signals and controlling the opening and closing of the exhaust valve 32 and the pressure relief valve 33. The controller 37 includes a timer and is configured to perform the following steps:

When S1 receives the signal that the liquid level has reached, it controls the air extraction valve 32 and the air release valve 33 to close;

The S2 timer starts timing. When a signal that the liquid level has not been reached is received within the preset time, the exhaust valve 32 is controlled to open after the preset time ends, and the process returns to S1. When no signal that the liquid level has not been reached is received within the preset time, the exhaust valve 33 is controlled to open.

A vacuum device is used to suction-cast the liquid rare earth metal to avoid oxidation of the rare earth metal during the casting process. The controller 37 is connected to the liquid level sensor 36, the air extraction valve 32 and the pressure relief valve 33 by signal, so that the air extraction valve 32 and the pressure relief valve 33 are controlled by the liquid level signal.

In a specific embodiment, the liquid height of the electrolyte in the rare earth electrolytic furnace is 50 cm, and the liquid height of the liquid rare earth metal is 12 cm. Since the density of the electrolyte is smaller than that of the liquid rare earth metal, the two can be layered in the electrolytic furnace. The height of the suction casting tube 20 is 80 cm, so the suction casting tube 20 can be inserted to the bottom of the liquid surface. The suction casting tube 20 sucks 50 cm of electrolyte, and the liquid level sensor is set at 30 cm from the upper end of the first riser 141. It should be emphasized that the volume from the bottom of the first riser 141 to the height of the liquid level sensor is greater than the volume of the electrolyte in the suction casting tube.

The mold cavity 10 includes a first mold cavity 11 and a second mold cavity 12, which are buckled together to form the mold cavity 10. A plurality of one-to-one corresponding molds 13 are arranged inside the first mold cavity 11 and the second mold cavity 12. The molds 13 are used to shape the liquid metal.

The inner side of the first cavity 11 and the second cavity 12 is also provided with a direct current runner 14 and a cross-flow runner 15. The direct current runner 14 is vertically arranged in the middle position of the inner side of the first cavity 11 and the second cavity 12. The cross-flow runner 15 is arranged downwardly inclined on both sides of the direct current runner 14 and is connected with each model 13. After the liquid metal of suction casting flows into the direct current runner 14, it is divided into each cross-flow runner 15 and flows into the model. The cross-flow runner 15 is arranged downwardly inclined. In this scheme, the angle is 15°, which is convenient for the liquid metal to slide down. The cross-flow runner 15 is arranged at the upper end of each model 13. The liquid rare earth metal flows downward into the model 13 after passing through the cross-flow runner 15, ensuring that the liquid rare earth metal in the model 13 does not flow out after deflation.

The upper and lower ends of the DC runner 14 are respectively provided with a first riser 141 and a second riser 142. In the present embodiment, the first riser 141 and the second riser 142 are both configured as conical or cylindrical risers with a diameter greater than 1.5 times that of the DC runner. The upper end of the first riser 141 is connected to the vacuum tube 30 via a first flange, and the lower end of the second riser 142 is connected to the suction casting tube 20 via a second flange. The provision of the risers avoids incomplete mold filling caused by excessive suction casting speed, thereby effectively alleviating turbulence.

The first riser 141 and the second riser 142 are fixed on the second cavity 12. The first cavity 11 is provided with a pouring mouth 111 adapted to the first riser 141 and the second riser 142. After the cavity 10 is buckled, the whole device is in a sealed state, ensuring that the interior can be vacuumed.

A cylinder 40 is provided outside the first cavity 11. The first cavity 11 and the second cavity 12 are positioned around by sliding guide rods 16. The cylinder 40 drives the second cavity 12 to slide along the sliding guide rods 16, and the first cavity 11 is fixed. The cylinder 40 is fixed on the lifting platform 50 and is used to adjust the depth of the suction casting tube 20 inserted into the electrolytic furnace.

The upper end of the electrolyte overflow box 34 is provided with a sealing cover, and the sealing cover is provided with an observation portion 341 for observing the overflow of the electrolyte. The observation portion 341 is made of a transparent material, such as glass. Since the liquid will be sucked into the vacuum tube 30 after vacuuming, the electrolyte overflow box 34 is set at the maximum suction casting height. In a specific embodiment, the vacuum pressure is 0.06Mpa, and the electrolyte overflow box 34 is set 1.4m from the end of the suction casting tube 20.

The vacuum tube 30 is also provided with a vacuum pressure gauge 35 for detecting the pressure value.

The cavity 10 is coated with titanium. Since titanium does not react with rare earth metals, impurities in the rare earth metals are avoided, thereby ensuring the purity of the rare earth metals.

Example 2

The suction casting method using the rare earth metal vacuum suction casting device described above, in conjunction with FIG4 , comprises:

Insert the suction casting tube 20 into the bottom of the metal receiver of the rare earth electrolysis furnace, and the cylinder 40 drives the second cavity 12 to slide and engage with the first cavity 11, so that the suction casting tube 20, the cavity 10, the first riser 141, the second riser 142, the vacuum tube 30, the electrolyte overflow box 34 and the vacuum tank 31 are sealed and connected;

Open the air extraction valve 32 and close the pressure relief valve 33;

When receiving the signal that the liquid level has reached, the controller 37 controls the air extraction valve 32 and the air release valve 33 to close;

The timer starts timing. When a signal indicating that the liquid level has not been reached is received within a preset time, the controller controls the air extraction valve to open after the preset time ends. When no signal indicating that the liquid level has not been reached is received within the preset time, the controller 37 controls the air release valve 33 to open to cool the liquid rare earth metal.

After the mold cavity 10 is cooled, the cylinder 40 drives the second mold cavity body 12 to slide so that the mold cavity 10 is opened and the rare earth metal is taken out.

The air extraction valve 32 is an electromagnetic air extraction valve. The electromagnetic vacuum valve is suitable for using liquid as the working medium and can control the on-off of the liquid working medium pipeline.

After the pressure relief valve 32 is opened and the air extraction valve 33 is closed, the liquid in the vacuum tube 30 and the suction casting tube 20 flows back to the rare earth electrolysis furnace.

The present invention adopts a vacuum device to suction-cast the liquid rare earth metal, thereby avoiding oxidation of the rare earth metal during the casting process. The controller is connected with the liquid level sensor, the air extraction valve and the pressure relief valve signals, and the air extraction valve and the pressure relief valve are controlled by the liquid level signal. Riser heads are arranged at the upper and lower ends of the DC runner to prevent turbulence when the air extraction starts. The device is used to suction-cast the liquid rare earth metal, and the purity of the rare earth metal is improved without electrolyte wrapping.

The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims (8)

1. A rare earth metal vacuum suction casting device, comprising a mold cavity, characterized in that it also includes: A suction casting tube is inserted into the lower end of the cavity; A vacuum tube, one end of which is plugged into the upper end of the cavity and the other end of which is connected to a vacuum tank, wherein the vacuum tube is provided with an air extraction valve for vacuuming and a pressure relief valve for pressure relief; An electrolyte overflow box is connected to the vacuum tube and is used to collect overflowed electrolyte. A liquid level sensor is provided at the lower end of the connection between the vacuum tube and the electrolyte overflow box. The liquid level sensor is used to output a signal of whether the liquid level reaches that location. A controller is connected to the liquid level sensor, the air extraction valve and the pressure relief valve signals, and is used to receive the signals and control the opening and closing of the air extraction valve and the pressure relief valve. The controller includes a timer and is configured to perform the following steps: S1 controls the air extraction valve and the air release valve to close after receiving the signal indicating that the liquid level has reached; S2: the timer starts timing, and when a signal indicating that the liquid level has not been reached is received within a preset time, the air extraction valve is controlled to open after the preset time has expired, and the process returns to S1, and when no signal indicating that the liquid level has not been reached is received within the preset time, the air release valve is controlled to open; The mold cavity comprises a first mold cavity and a second mold cavity, and a plurality of one-to-one corresponding models are arranged inside the first mold cavity and the second mold cavity; The inner sides of the first cavity and the second cavity are also provided with a direct current runner and a cross-flow runner, wherein the direct current runner is vertically arranged at the middle position of the inner sides of the first cavity and the second cavity, and the cross-flow runner is arranged downwardly at both sides of the direct current runner and is connected to each of the molds; The upper and lower ends of the DC runner are respectively provided with a first riser and a second riser, the upper end of the first riser is connected to the vacuum tube through a first flange, and the lower end of the second riser is connected to the suction casting tube through a second flange; The first riser and the second riser are fixed on the second cavity, and the first cavity is provided with a pouring mouth adapted to the first riser and the second riser; A cylinder is disposed on the outer side of the first cavity. The first cavity and the second cavity are positioned around by sliding guide rods. The cylinder drives the second cavity to slide along the sliding guide rods. 2. The rare earth metal vacuum suction casting device according to claim 1 is characterized in that the cylinder is fixed on a lifting platform and is used to adjust the depth of the suction casting tube inserted into the rare earth electrolytic furnace. 3. The rare earth metal vacuum suction casting device according to claim 1 is characterized in that a sealing cover is provided at the upper end of the electrolyte overflow box, and an observation part is provided on the sealing cover for observing the overflow of liquid metal, and the observation part is made of a transparent material. 4. The rare earth metal vacuum suction casting device according to claim 1, characterized in that a vacuum pressure gauge is also provided on the vacuum tube for detecting the pressure value. 5. The rare earth metal vacuum suction casting device according to claim 1, characterized in that there is a titanium coating in the cavity. 6. A suction casting method using the rare earth metal vacuum suction casting device according to any one of claims 1 to 5, comprising: Insert the suction casting tube into the bottom of the metal receiver of the rare earth electrolytic furnace, and drive the second cavity to slide and engage with the first cavity, so that the suction casting tube, the cavity, the first riser, the second riser, the vacuum tube, the electrolyte overflow box and the vacuum tank are sealed and connected; Open the air extraction valve and close the pressure relief valve; When receiving the signal that the liquid level has reached, the controller controls the air extraction valve and the air release valve to close; The timer starts timing. When a signal indicating that the liquid level has not been reached is received within a preset time, the controller controls the air extraction valve to open after the preset time ends. When no signal indicating that the liquid level has not been reached is received within the preset time, the controller controls the air release valve to open to cool the liquid rare earth metal. After the cavity is cooled, the cylinder drives the second cavity to slide to open the cavity and take out the rare earth metal. 7 . The suction casting method according to claim 6 , wherein the air extraction valve is an electromagnetic air extraction valve. 8. The suction casting method according to claim 6, characterized in that after the pressure relief valve is opened and the air extraction valve is closed, the liquid in the vacuum tube and the suction casting tube flows back to the rare earth electrolysis furnace.