JPS5926876B2 - Gasdynamic stirring method and device for molten liquid metal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the metallurgical industry, and more particularly to a method for stirring molten liquid metal directly in a metal bath of a melting furnace.

This agitation is performed to speed up the melting process, promote homogenization of the chemical composition of the molten metal body, and enhance uniform temperature distribution of the molten metal body. Direct stirring of liquid metal in the bath of an Imade melting furnace is already known in the art, ie mechanical, electromagnetic, gas-dynamic methods, etc.

The present invention is the simplest and most preferred of these methods, and relates to a method for gas-dynamically stirring liquid metals, particularly corrosive metals such as aluminum alloys. Although the conventionally known general methods have been somewhat favorable in terms of the productivity of the melting process, they are not without serious drawbacks.

That is, a constant time interval between compressed gas pulses acting on the metal part of the tube is an optimal condition for one stage, but not for the other two stages. . Furthermore, the energy of the compressed gas cannot be fully used to accelerate the metal within the tube to the desired velocity.

This can be explained by the fact that a significant portion of the energy of the compressed gas pulse is spent retaining the metal within the tube during the period of wicking the metal from the bath. A portion of this energy is spent directly holding the metal, while another portion is spent isolating the suction from the working cavity of the pump. Only the remainder of the pulse's energy is then used to accelerate the metal to a certain speed. Obviously, it is often not possible in practice to obtain the desired rate of metal outflow from the tube, but the rate is essentially the effect of agitation of the metal. On the other hand, it is not at all desirable to increase the initial energy of the compressed gas pulse, since the reaction of the metal rising into the tube and the compressed gas flow inhibiting the progress of the metal generally results in some gas penetration into the metal. It turns out that if the pulse energy increases, gas will become included in the metal, which is undesirable.

The invention provides a method for producing molten metal, e.g. and the process of stirring the alloy thereof.

A method and apparatus for stirring molten metal is disclosed in U.S. Pat.
, 008,884 (Cl. 266-233).

This method of agitating molten metal consists of sucking soil from the molten metal body into a confined space, such as a tubular vessel, up to a certain level above the molten metal body in a bath, and The jet is fired into the molten metal body as a high-velocity jet that sinks the molten metal that has been sucked up to agitate the metal body, and at a distance that the jet substantially exceeds the depth of the metal body, it penetrates the lower part of the metal body. and horizontally oriented steps.

According to this known method, alternating suction and firing steps supply suction and pressurized gas into a confined space in the molten metal body (i.e. the top part of the tubular container). The suction of the liquid metal is carried out through an orifice in the vessel below the molten metal body, and the injection of the sinking jet is carried out horizontally within the lower region of the metal body.

Furthermore, the above method provides a suction signal by measuring the suction value at the top of the container, adjusts the duration of the suction step according to the suction value maintained at a preset level, and injects melt into the container. Contact the suction device to raise the metal in the state, determine the level of metal to be raised,
Each saturation step is then based on terminating the supply of suction power when the metal is raised to a predetermined level.

According to the technical concept disclosed in the above-mentioned US Pat. No. 4,008,884, an apparatus for stirring molten metal has a tubular container, and a molten metal body is disposed at the lower end of the tubular container. A nozzle is provided at the upper end of the tubular container, which sucks up the metal (by suction) into the container up to a certain level of the molten metal, and by the action of the gas, the nozzle is inserted into the container. A device (stirring type) is provided that alternately fires the metal sucked up into the molten metal body.

This gas, air, is supplied from the air reservoir to the stirring device via a fill and discharge solenoid valve. The sequence of fill and discharge operations is controlled by a vacuum switch and an electric timer.

In order to preset the maximum permissible rise level of the molten metal, an electrical level sensor is arranged in the interior cavity of the tubular vessel, which is connected to a switch-off relay. However, the above-mentioned known methods and devices for pneumatically stirring molten liquid metals have the disadvantage that to some extent their field of application is limited.

The fixed arrangement of the pump tube in the furnace bath provides active agitation to a limited extent, so that in large capacity furnaces a large number of pumping devices are required.

When metals are melted in round or rectangular furnaces, at least two pumps must be installed even in furnaces of relatively small capacity in order to obtain sufficiently rapid melting and dissolution of the alloying additives.

On the other hand, it is often difficult to arrange a large number of pumps in a melting furnace (
There are various disadvantages, not to mention the increased consumption of compressed air. The wicking or firing of the metal at a given height on the ground of the hearth allows the great potential of the above method to be exploited to the fullest possible extent with a view to maintaining optimal conditions for heat and mass exchange. It becomes a hindrance. This disadvantage becomes especially apparent in the case of melting solid fillings when the temperature of the metal in the molten state is relatively low, and as far as the melting rate and the utilization of heat in the furnace are concerned, Washing the solid mass of the filling with a metal jet may not produce optimal results. In furnaces containing metal bodies in a fairly deep molten state, the methods known in the art have not been able to give the best results. In this case, it is considerably difficult to position the pump optimally perpendicular to the molten metal body, with the level of the molten metal body varying over a relatively wide range. Furthermore, the energy of the compressed gas pulse is such that the action of the compressed gas begins either when the liquid metal is rising up the tube of the pump or, in the best case, when the liquid metal is at rest within the tube of the pump. Because of this situation, they are unable to utilize their full potential.

It is not possible to obtain the maximum velocity of the metal jet produced in the tube of the pump at a given gas pressure. In a state where the gas pressure increases, the energy cost factor increases, and furthermore, in this state, the state in which gas is mixed into the metal increases. Operation with a preset vacuum or suction value controlled by a suction switch for each individual pump cannot significantly speed up the suction of metal parts into the tube of the pump, i.e. It is not possible to shorten the time of the wicking process.

Furthermore, generating the suction by means of an agitation device attached to the pump and activated only after the supply of compressed gas pulses via the respective solenoid control valves obviously increases the time required to siphon the metal into the tube. let In this case, there is no effect of speeding up the suction of metal into the tube of the pump. The two last-mentioned factors are effective in the operation of the pump, especially in the phase of melting the solid charge, when it is necessary to increase the frequency of alternating pump-fire cycles. The main object of the present invention is to improve the gas dynamics of liquid metals in the molten state in order to increase the efficiency of agitation of liquid metals in high-capacity melting furnaces and to overcome the disadvantages of previously known methods and devices used for similar purposes. It is an object of the present invention to provide a method and apparatus for stirring the same.

The present invention solves the technical problem of harmonizing the forces applied to the pumped metal part in the tube of the pump so as to provide maximum efficiency for ejecting the metal into the molten metal body at an accelerated rate. is the purpose.

The purpose of this invention is to suck up a metal part from a molten metal body into a tube of a pump by using a suction and to remove a metal part from a molten metal body by applying a pulse of compressed gas to the metal part. In a method of aerodynamic agitation of liquid molten metal, which alternates steps of ejecting the metal into the body, the action of the suction is stopped just before supplying the pulse of compressed gas to the tube of the pump, and the ejected metal part is This is achieved by a method of gas-dynamic stirring of liquid molten metal, which is characterized by allowing it to fall naturally due to gravity.

This technical solution allows the compressed gas pulse to be applied to the wicked metal part, which has already begun to fall under gravity, in order to create the necessary conditions for accelerating the metal part launched into the metal body to a relatively high velocity. can increase the effect of stirring the molten metal in a high-capacity furnace. In this case, the entire energy of the compressed gas pulse is spent accelerating the metal part, which already has a certain initial velocity, so that the metal jet from the tube of the pump leaves at a relatively high speed, This makes it possible for the metal jet to reach relatively long distances within the molten metal body, which is important in high capacity plants. Having the compressed gas pump act on the projectile metal reduces the amount of gas entrained in the metal compared to when the movements oppose each other. It is preferred to communicate the cavity in the tube of the pump above the metal part to the atmosphere prior to applying a pulse of compressed gas to cause the wicked metal part to exit the tube.

The above arrangement makes the use of compressed gas energy more economical, since the holding and pre-acceleration of the wicked metal part is effected by atmospheric energy, and the metal is pre-accelerated in this case only by gravity. It can be used for.
The energy of the compressed gas O pulse is then all expended to accelerate the already moving metal parts in the tube, thus increasing the rate of ejection of the metal jet from the tube, and reducing the amount of metal in the molten state. The trajectory of the jet in the body can be extended, and the five stirring steps can be made more intense. Furthermore, it is preferred that the compressed gas pulse is timed to the onset of the free fall of the metal part.

This configuration is advantageous because the compressed gas flow takes only the minimum necessary passages to encounter the liquid metal in the tube that has already begun its descent, so that all the energy is spent accelerating the metal. The energy of compressed gas can be utilized to the highest degree.

Furthermore, a tube with a removable cover, a device for supplying pulses of compressed gas from the pressure accumulator via a distribution device to the outlet nozzle, a suction device for sucking up the metal part and having a suction force cut-off device, and the metal in the molten state. In a device consisting of a sensor for detecting the metal level in a bath, the outlet nozzle is arranged in a movable annular sleeve oriented upwardly in the direction of the cover of the tube of the pump and provided with a shoulder, in which said cover is fitted with a rod. When a valve is installed, said rod-type valve cooperates with said shoulder of a movable sleeve to communicate the inner cavity of the tube with the atmosphere, and when said valve is raised by said movable sleeve, said movable sleeve The method of gas-dynamic stirring of molten liquid metal disclosed herein may be accomplished using a device characterized in that it is operatively coupled to a float submerged in a rising molten metal portion. preferable.

This type of device allows the pump to be installed without modification in a high-capacity melting furnace, and yet connects and connects the internal cavity of the pump with the atmosphere supplied into the cavity, thereby closing the tube. Having a device for acting on the energy of the elevated metal part can provide the necessary conditions for sufficient stirring.

Operationally coupling this device to the metal through a float means that the internal cavity of the pump is communicated with the atmosphere on each successive cycle of siphoning a metal part into the tube, so that the approaching compressed gas pulse It can be ensured that the necessary conditions for ejecting the metal jet from the tube at high velocity when acting on the section can be provided in advance. The cover of the pump is provided on its inner surface with a device for dispersing the gas flow in a tapered manner extending into an annular toroidal cavity arranged axially of the outlet nozzle and in which a rod-shaped valve is arranged in the recess. Preferably.

With this construction, the compressed gas flow is distributed and uniformly distributed over the entire cross section of the tube of the pump;
By applying a pulse of compressed gas to the metal, conditions can be created to reduce the entrainment of gas into the metal being fired.

Preferably, the float is connected to the movable annular sleeve by links connected to each other with adjustable length and removable devices. This structure allows different lifting speeds for sucking metal parts into the tube by adjusting the space between the float and the sleeve and by selecting the optimum relative position according to the lifting speed. can operate the pump.

Furthermore, the float and sleeve can be removed whenever necessary. An electrical contact device in the form of a probe is attached to the cover of the pump tube, and the probe is wired to a circuit that controls the supply of compressed gas pulses.
The length of the probe within the internal cavity of the tube is selected such that the passage time of the wicked metal part along the probe up to the time of the rise of the rod-type valve exceeds the time of response to the compressed gas pulse supply device. has been done.

With this construction, it is possible to speed up the rate of rise of the metal in the tube of the pump so that it can be operated at suction values such that the metal can theoretically be lifted above the cover of the pump.

In this case, the start of the compressed gas pulse can occur simultaneously with the start of the gravitational descent of the metal part without the need for additional monitoring and control equipment. Furthermore, the probe of the electrical contact device can be attached to the cover of the pump tube by means of a collector chuck that can adjust the axial protrusion of the probe. This structure allows for the extent of the rise of the metal along the probe to be controlled, while also allowing the onset of the compressed gas pulse to be precisely timed with the onset of the gravitational descent of the metal part.

Furthermore, the outlet nozzle has a suction force cutoff device at its inlet, which suction force cutoff device is connected in parallel to the metal part suction device by suction force and the compressed gas pulse supply device, and the suction force cutoff device is connected in parallel to the suction force metal part suction device and the compressed gas pulse supply device. The device has another movable nozzle mounted as a valve member of the outer conical nozzle and movable relative to the conical nozzle by a spring, the force of which is adjusted to interrupt the flow passage. Moreover, it is adjusted to set one nozzle within the other nozzle when the compressed gas pulse is supplied.

This configuration allows the vacuum or suction device to disengage from the internal cavity of the tube of the pump during application of the compressed gas pulse, but does not prevent the initiation of the gravitational descent of the metal within the tube, thereby preventing the onset of the compressed gas pulse and the metal The influence of the suction device can be eliminated by the conditions provided to time the start of the descent of the part due to gravity.

Furthermore, this configuration allows for easy adjustment of the precise timing of the two actuations. Furthermore, the above arrangement speeds up the operation of the device since no special or timing devices are required to connect the suction device to the internal cavity of the tube of the pump once the action of the compressed gas pulse has ended. Therefore, the productivity of the pump can be improved.

On the other hand, the frequency of the cycles can in this case be adjusted by incorporating a regulating throttle which regulates the rate at which the suction force is generated in the tube and, as a result, the rate at which the metal part is drawn up from the molten metal body. Adjusted quickly.
Preferred embodiments of the present invention will be described with reference to the drawings.

The implementation of a gas-dynamic agitation process according to the disclosed method is illustrated schematically in Figures 1 and 2, in which the tubes of the pump correspond to each successive stage of the pump's operating cycle. An operating cycle diagram of the pump in relation to the advancement of metal within the pump is shown.

■ is the advancing speed of the metal in the tube, and ゛+゛d-゛ indicate the rise and fall of the metal, respectively.

τ indicates time. P1 and P2 are pressure values corresponding to the main pulse /1/ and the auxiliary pulse /2/, respectively.

The dotted lines in the drawings indicate for comparison the acceleration of metal within the tube according to prior art methods.

A metal part 3 (a predetermined value) is siphoned off. The metal part inside the tube is under pressure P
2 by means of an auxiliary pulse of compressed gas, for example air at atmospheric pressure, in which case the supply of the suction is simultaneously cut off from the operation inside the tube of the pump. This causes the metal's rising speed to be zero, so that it stops in the tube at a predetermined level, after which it descends in the tube and gains an initial speed of movement in the opposite direction. At this time, a control signal, ie, a signal sent by the contact level sensor, initiates the delivery of a main pulse of compressed gas that accelerates the metal in the tube to a predetermined velocity. The metal jet penetrates into the molten metal body at this speed and engages the adjacent metal layer, thus stirring the molten metal body and the metal. Implementing the method disclosed in the text with two pulse timing feeds is a special feature of simultaneously cutting off the supply of suction and starting the supply of the auxiliary pulse at a pressure that does not allow gas to mix with the metal in the tube. Depending on the device, either manual control from control pulses or from a control computer is possible.

Preferably, the method of the invention is carried out with the auxiliary pulse following the main pulse with a delay that equalizes the transit time of the control actuation through the system. An embodiment of the method of the invention is described for melting an aluminum alloy;
The molten metal body is stirred at each melting stage in a 30 ton capacity melting furnace.

The pneumatic pump is operated with a supply rate or frequency of compressed gas pulses in the range of 4 to 20 pulses/min.

As the metal part within the tube is ejected or accelerated into the molten metal body, the metal part is acted upon by two pulses sequentially. The first or auxiliary pulse results in air at one atmosphere (absolute) or atmospheric pressure by simultaneously cutting off the supply of suction to the working cavity and communicating the working cavity to the atmosphere. This results in a rate of rise of the metal in the tube, which decreases from 1.2 m/s (suction at 0.4 atm) to zero, following the start of the auxiliary pressure coupler supply to 0.6 m/s.
・・・・・・Changes to descent in 0.8 seconds.

Thus, 0.5 seconds after the start of the auxiliary pulse supply, the control signal is sent, and about 0.1 seconds thereafter the actuating member, i.e. the distribution device, responds, and 5. At O atmosphere the main pressure coupler remains at O. until the end of the action of the main compressed gas pulse. From an initial velocity of 5 m/s (following the end of the action of the auxiliary pulse) approximately 3.5 m/s
accelerated the metal to s. In the above method, an acceleration of the metal part is carried out in order to effect gas-dynamic stirring at each melting stage, irrespective of the feed rate of the pressure pulse, and the method of the invention has an acceleration of 10% compared to the prior art method. can shorten the melting time.

The stirring state is maintained until the molten metal is poured into the mixer.

The above-described examples of carrying out the method are not intended to limit the parameters of the process nor to exclude other ways of carrying out the claimed method.

Experiments have shown that the method of the invention allows for increased agitation efficiency and reduced melting time by 1570 degrees.

The directions of movement of metal and gas flows are shown in Figures 3 and 4.
It is indicated by an arrow in the figure and FIG.

In a preferred embodiment, the pump for pneumatically agitating the liquid metal 5 in the bath of the furnace 6 is provided with a removable cover 8.
and a nozzle 9 with an outlet directed towards the cover 8
It includes an internal lined tube 7 with an internal liner. The nozzle 9 is connected via a pipeline 10 to a device 11 which disconnects the supply of vacuum or suction from the tube. Device 1
1 is in operative communication with a distribution device that controls the supply of pulses of compressed gas (nitrogen, algol, etc.) from the pressure accumulator 13. The pressure accumulator 13 has an appropriate volume which adjusts its volume according to the pressure of the gas and is maintained by the pressure regulator 14. The internal working cavity of the tube 7 is permanently connected via a nozzle 9, a pipeline 10 and an injector or device 11 with a suction line 15 with a controllable throttle 16, said throttle 1
6 can adjust the rate of rise of metal in the tube. A contact sensor (not shown) is provided to detect the metal level within the tube and is wired to send a control signal to the solenoid of the distribution valve 12. The cover 8 has a tapered dispersion device 17 for distributing the gas flow, which dispersion device 17 is arranged in the axial direction of the nozzle 9 and has a toroidal annular recess 18 for stabilizing the gas flow in the tube of the pump. form. The nozzle 9 is surrounded by an annular sleeve 19 with a shoulder movable along the nozzle 9. The sleeve 19 abuts a longitudinally adjustable ring 20 of the nozzle 9 and in this way the sleeve 19 and the cover
8 is set. Sleeve 19 is operatively connected to float 22 by length adjustable link 21. This coupling device can adjust the spacing between the sleeve 19 and the float 22 and thus time the time when the sleeve 19 seals away from the suction line and opens the working cavity to the atmosphere. can. The float 22 is made of a lightweight refractory material, such as asbestosthermosilica.
It is preferably made of a material such as te) or may be a hollow member if it is made of a metal that does not dissolve in the alloy being stirred. Float 22 is preferably streamlined to minimize obstruction to gas flow. The float has an arcuate top or a truncated bottom and is shaped like a droplet, such as a cone. A rod-type valve 23 with a disk 24 is suspended freely from the cover 8, which disk 24 is able to seal off a passage 25 communicating the working cavity of the tube 7 with the surrounding atmosphere. In another embodiment of the device, this communication is not with atmosphere, but with an air chamber filled with gas at a gauge pressure less than the pressure in the pressure accumulator to provide 8 "soft" pulses. The pump disclosed in this text operates as follows.

The bath of the furnace 6 is filled with metal 5 to a level where the outlet of the tube 7 is not exposed, the suction line 15 is connected to the internal working cavity of the tube 7, the pressure accumulator 13 is connected to the distribution valve 12 and the pressure regulator 14. to a source of compressed gas. At the same time, voltage is applied to the coil of the solenoid of distributor valve 12 so that the contact sensor lot
6 and the relative positions of the float 22 and the sleeve 19 are lowered to a predetermined level. The suction raises the liquid metal in tube 7 to a certain height,
The float 22 with the sleeve 19 is thereby raised. Finally, the sleeve 19 raises the rod-type valve 23 by means of its shoulders, the plate or valve member 24 opens a passage 25 communicating the interior of the tube with the atmosphere, and the sleeve 19 connects the working cavity of the tube with the suction source. Begin to seal communication between them. The metals rise at a slow rate, and at a given time they stop due to the upward force resulting from the pressure drop, and the weights of the metals balance each other out. At this time, the contact level sensor responds and the solenoid of the distributor valve 12 is actuated, which causes the pressure accumulator 13 to communicate with the working interior of the tube 7 via the injector 11, the pipeline 10 and the nozzle 9. The injector 11 then stops supplying the suction and the compressed gas from the pressure accumulator 13 immediately flows into the working cavity. The pressure pulse acts on the metal body within the tube and fires the pressure pulse at high velocity into the molten metal body within the bath. The duration of the pulse is extended appropriately by the equipment used for this purpose. The metal parts ejected from the tube in high velocity jets travel through the bath and contact adjacent layers of the molten metal body, in such a way that the entire molten metal body is agitated in the bath. When the metal in the tube leaves the contact sensor rod, the solenoid of the distribution valve 12 is deactivated and compressed gas is supplied to the pressure accumulator 13 from the compressed gas source.

Another portion of liquid metal is then drawn into the tube by the suction and the above cycle of operation of the device is repeated. The device according to the invention can operate equally effectively whether the tube of the pump is stationary or movable.

The pump disclosed herein can increase the efficiency of the melting process and reduce the melting time by 1570 degrees, for example for aluminum alloys.

In the embodiment described below, a main contact level sensor is mounted on the cover 26 of the device, the probe 27 of which is connected to one contact of the solenoid of the dispensing device 28 and the other contact is connected to a voltage of 12V.

The metal objects in the bath are grounded, so when the metal contacts the probe 27, the solenoid of the distributor is activated, completing line 12 Voltage Source-Azo. The probe 27 of the contact sensor is mounted on a nut-tightening collector chuck 29 which allows the distance of the probe from the cover 26 to be easily adjusted and thus the working volume of the working cavity of the tube 30. By throttling, it is possible to adjust the time to achieve the desired subatmospheric pressure in the working cavity of the tube, and thus the rate of rise of the metal to a preset height. This embodiment of the device can operate as follows.

Filling the furnace bath with molten metal to a predetermined acceptable level without exposing the outlet of tube 30, a vacuum or suction line 31 is connected to the working cavity of tube 30, and a pressure accumulator 32 is connected to distributor 28 and pressure It is connected to a compressed gas source via a calegulator 33. At the same time, voltage is supplied to the coil of the solenoid of the distribution device 28 and the probe 27 of the level sensor follows the setting of the throttle member which regulates the rate of rise of the metal in the tube 30 at the pressure cursor suction below a predetermined atmospheric pressure of the suction device. and then lowered to a predetermined level. The liquid metal is raised by the suction in the tube 30 to a preset height where the liquid metal contacts the probe 27 of the contact sensor, thereby completing the line ``ground-12V power'' and distributing the device. 28 solenoids are activated.

A pressure accumulator 32 is connected to the working cavity of the tube 30 via a line 31 and a nozzle 34, and the compressed gas stored in the pressure accumulator 32 flows rapidly into the working cavity. The compressed gas pulse acts on the metal body within the tube and fires the pulse at high velocity into the metal body of the bath. A portion of the liquid metal ejected from the tube passes through the metal body in the bath and contacts the adjacent layer of metal, thereby stirring the entire metal body in the bath. When the metal in the tube leaves the probe 27, the completed line 1 ground power is turned off, the solenoid of the distributor 28 is deenergized, and compressed gas begins to flow from the pressure line 35 into the pressure accumulator 32.

The liquid metal is then drawn into the tube again by the suction and the above cycle of operation of the device is repeated. With the above-described construction of a device for stirring liquid metals, high efficiency and capacity can be obtained due to the full utilization of the working volume of the tube even at relatively high suction values in the suction device.

Furthermore, the following detailed description is of a preferred embodiment of a suction force isolation device for a pneumatic pump.

The suction cut-off device of the pneumatic pump stirring the molten metal has a chamber of fixed nozzles 36. A movable nozzle 37 is arranged within the nozzle 36, the movable nozzle 37 being connected to the dispensing device 28 via a line 31 (FIG. 6);
The distribution device 28 supplies pulses of compressed gas (nitrogen, argon, etc.) from a pressure accumulator 32 which is filled through a pressure regulator 33 from a pressure supply line. A resilient member, such as a compression spring 44, which maintains the nozzle 37 in a suspended or floating condition, is located between the annular groove 39, which joins the tapered surface 40 of the chamber, and the shoulder 38 of the nozzle. The gap between the end face of the nozzle 37 and the tapered surface 40 is adjusted by a lid 41 screwed onto the nozzle 36. The outlet portion of the nozzle 37 is formed with a passageway 42 which connects a cavity 43 between the outer surface of the nozzle 37 and the inner surface of the chamber of the nozzle 36 to the compressed gas pulse supply line. The device operates as follows. In the initial position shown in FIG. 8, suction line 31 communicates with the chamber of nozzle 36 and compressed gas is supplied via distribution device 28 to pressure accumulator 32 (FIG. 6).

When the distribution device 28 is switched, the compressed gas stored in the accumulator 32 flows through the line 31 into the nozzle 37 (FIG. 8). As the gas passes through the nozzle 37, a pressure drop occurs across the nozzle. At the same time, the compressed gas flows through the passage 42 into the chamber 43 and acts on the area formed by the shoulder surface of the nozzle. The nozzle 37 is moved by the pressure of the compressed gas on the shoulder 38 so that the end face of the nozzle 37 abuts the tapered surface 40 of the passage and the suction supply line is cut off from the interior cavity of the tube. Spring 44 is compressed by the same force and remains compressed until the end of the compressed gas pulse. At the end of the pulse, spring 44 returns nozzle 37 upward to its initial position. The above operating cycle is then repeated in the same sequence of steps.

The last structure described relates to both fixed and movable pump tubes, and its incorporation increases the productivity of pumps using suction plants by an average of 8...1070 points. be able to.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the state of the metal part drawn into the tube of the pump, Figure 2 is a chart showing the variation of the speed of movement of the metal part being returned to the molten metal body versus time, and Figure 3 is the control a longitudinal sectional view of the stirring device schematically showing the system; FIG. 4 is a sectional view of the end portion of the tube associated with the valve of the device shown in FIG. 3 during the supply of compressed gas pulses; Figure 5 is a sectional view of the end portion of the tube associated with the valve of the apparatus shown in Figure 3 when the interior of the tube is in communication with the atmosphere; Diagram for the control system for supplying gas pulses, No. 7
The figures show a cross-sectional view of the mounting device for attaching the electrical contact device or probe to the cover of the device shown in FIG.
The figure is a sectional view showing the suction force cutoff device of the device shown in FIG. 3. 2...Pump, 3...Metal part, 5.
...melted metal body, 7 ... tube of the pump, 8 ... removable cover of the pump
9... Outlet nozzle, 12... Distribution device (valve), 13... Pressure accumulator, 19.
... Sleeve, 22 ... Float, 23
・・・・・・Rod type valve, 21 ・・・・Rictional valve, 1
7... Dispersion device, 26... Cover 2
7...Probe, 29...Collection chuck, 30...Tube, 37...
Movable nozzle, 36...Fixed nozzle, 44...
...Spring.

Claims (1)

[Scope of Claims] 1. Sucking a metal part from a molten metal body into a tube of a pump using suction force, and removing said metal part by applying a pulse of compressed gas to said metal part. In a method of gas-dynamic stirring of molten liquid metal, which alternates steps of firing the metal body in the molten state, the action of the suction force is stopped immediately before supplying the pulse of compressed gas into the tube of the pump 2. , the space of the tube of the pump 2 above the metal part 3 is communicated with the atmosphere, the raised metal part 3 is allowed to fall naturally by gravity, and the compressed gas pulse is supplied naturally by the gravity of the metal part 3. Gas mechanics of molten liquid metals, which occurs simultaneously with or immediately after the start of the descent, so that all of the energy of the compressed gas pulse is spent accelerating the already moving metal parts in the tube. Stirring method. 2. a tube with a removable cover, a device for supplying pulses of compressed gas from a pressure accumulator via a distribution device to an outlet nozzle, and a suction force cutoff device;
In a device for aerodynamic stirring of molten liquid metal, consisting of a suction device for the metal part and a cesser for detecting the metal level in the molten metal bath, the outlet nozzle is directed upwardly in the direction of the cover 8 of the tube of the pump. The rod-type valve 23 is received in a movable annular sleeve 19 with a shoulder and a shoulder.
3 cooperates with the shoulder of the movable sleeve 19 to open the inner cavity of the tube 7 to the atmosphere, so that when the valve 23 is raised by the movable sleeve 19, the movable sleeve 19 is raised. 1. A pneumatic stirring device for molten liquid metal, characterized in that it is operatively connected to a float 22 submerged within a portion of molten metal. 3. A device 17 for distributing the gas flow in a tapered manner is provided on the inner side of the cover 8, and the dispersing device 17 is disposed in the axial direction of the outlet nozzle 9 and disposed in the cavity of the cover. Device according to claim 2, characterized in that it extends into an annular toroidal recess (18) with a rod-type valve (23). 4. According to claim 2 or 3, the float 22 is connected to the movable annular sleeve 19 by length-adjustable links 21 removably connected to each other. A device for gas-dynamic stirring of molten liquid metal as described. 5 The cover 26 of the tube of the pump is connected to the probe 27
mounting in said cover 26 an electrical contact device of the form and connected to a circuit for controlling the supply of compressed gas pulses;
The length of the probe 27 within the internal cavity of the tube is such that the length of the probe 27 within the internal cavity of the tube is such that the length of the probe 27 within the internal cavity of the tube is
The passage time of the metal part sucked up along the compressed gas pulse supply device is selected such that it is longer than the response time of the compressed gas pulse supply device. Gas-dynamic stirring device for molten liquid metal. 6 The probe 27 of the electrical contact device is the probe 2
7. The gas-dynamic pump of molten liquid metal according to claim 5, characterized in that it is mounted in the collector chuck 29 and on the cover 26 of the tube of the pump for adjusting the axial projection of the molten liquid metal. Stirring device. 7. The outlet nozzle has at the inlet part of the outlet nozzle a suction force cutoff device connected in parallel with the device for sucking up the metal part by a suction and the compressed gas pulse supply device, and the suction force cutoff device has a movable nozzle 37 mounted as a valve member in another conical outer nozzle 36 and movable relative to said outer nozzle 36 by means of a spring 44, the force of the spring 44 interrupting the flow path. According to claims 2 to 6, the nozzle 37 is adjusted to set one nozzle 37 in the other nozzle 36 and block the flow path when the compressed gas pulse is supplied. gas-dynamic stirring device for molten liquid metal.