JP2005088070A - Pump, device and method for transferring molten metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molten metal transfer means which can maintain cleanliness at least by preventing the oxidation, gas absorption and the like of molten metal during transfer and prevent the contamination of the molten metal at the end point of transfer, and which has versatility not limiting a start point of transfer and an end point of transfer. <P>SOLUTION: The invention relates to a pump for transferring the molten metal by siphonic action. The molten metal transfer pump 1 is equipped with a chamber 2 having a specified space, a suction pipe 4 and a discharge pipe 3 which communicate with the chamber 2, a decompressing means which decompresses the chamber 2, and a connection port opening/closing means which is placed in a connection port between the discharge pipe 3 and the chamber 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a molten metal transfer pump using a siphon action that can be transferred while maintaining the cleanliness of the molten metal, and a molten metal transfer method.

When a casting product is obtained by molding using a casting method, the molten metal is first discharged from the melting furnace and held, for example, until the metal is melted or melted in the melting furnace to obtain the molten metal and molded in the mold. It is transferred to a furnace and kept warm, and then it is discharged from the holding furnace to the ladle and supplied to the casting mold by the ladle. Alternatively, in the case of the low pressure casting method, the molten metal is discharged from the melting furnace, transferred to the holding furnace and kept warm, and then transferred from the holding furnace to the holding furnace in the vicinity of the casting mold and pushed up from the holding furnace at a low pressure to be a casting mold. Supplied to.

At the time of transfer of the molten metal, problems that should be avoided such as entrainment of air and formation of oxides and absorption of hydrogen gas may occur. Therefore, various proposals have conventionally been made for transfer of the molten metal.

For example, according to Patent Document 1, a method of transferring hot water of a low-pressure casting machine has been proposed. In this proposal, one pipe port of the pipe body is placed on the surface of the hot water receiving side container stored in the holding furnace of the casting machine, and the other pipe port is placed in the molten metal of the transfer side container to hold the casting. The inside of the furnace is depressurized and the hot water transfer is started, and the molten metal on the hot water transfer side moves toward the hot water receiving side by the depressurization, fills the inside of the pipe, the hot water surface on the hot water receiving side rises, This is a method characterized in that the hot water transfer is continued by siphon action after exceeding the temperature, and since the molten metal does not entrain air in the pipe at the start of the siphon hot water transfer, the molten metal oxidation and gas absorption are performed during the hot water transfer. Because the atmosphere in the furnace when the molten metal falls on the surface of the hot water receiving vessel is a rare gas, it is possible to reduce the generation of oxides and gas absorption, and no pressure reducing pipe is provided. Therefore, it is possible to prevent the valve from being blocked.

According to Patent Document 2, a transfer pipe type hot water supply device and the like have been proposed. This proposal is provided with a molten metal transfer pipe that connects a molten metal holding section consisting of a distribution pipe or an independent furnace and an injection sleeve of a die casting machine, and the molten metal transfer pipe communicates with the end of the distribution of the molten metal, and the molten metal. It has a suction pipe consisting of a siphon section and a molten metal pulling section that are in cross communication with the transfer pipe, the siphon section is immersed in the molten metal in the molten metal holding section, the molten metal drawing upper section is connected to a vacuum device, and the molten metal transfer pipe is drained. It is a device that features a metering pouring valve device at the side end, which can simplify the structure and reduce the size, improve the heat transfer efficiency by the heater, and prevent leakage of the molten metal It is said that there is an effect that can be.

Further, according to Patent Document 3, a method for transferring a molten metal is proposed. In this proposal, a hot water supply pipe is bridged between a first container in which molten metal is stored and a second container in which molten metal is to be discharged, and the end of the hot water supply pipe is connected to the first and second containers. The method is characterized in that the molten metal in the first container is sucked through the hot water pipe and supplied to the second container by immersing in the molten metal and depressurizing the hot water pipe. It can prevent air entrainment during hot water supply, melt oxidation accompanying it, and oxide mixing into products, and there are few surfaces where the melt touches air, which can also prevent melt oxidation and receive melt By providing a hot water supply pipe for each container, there is an effect that, even when the type of molten metal is changed, there is no effect of causing component contamination due to the difference in alloy.
JP-A-7-195166 JP 7-290223 A JP 2000-117418 A

However, the above-mentioned conventional proposal for transferring the molten metal by siphon action has various problems as described below.

In the proposal disclosed in Patent Document 1, since the molten metal depressurizes the casting holding furnace on the hot water supply side and sucks and moves the molten metal from the container on the hot water supply side, there is a problem that it takes time to transfer. is there. In addition, the decompression device is increased in size and causes an increase in equipment cost, and the energy consumption required for decompression is large and the operation cost is increased. Furthermore, the pressure in the casting holding furnace (pouring into the mold) and the pressure reduction for the transfer are combined with one pipe, so that they are restrained from each other, the production efficiency is lowered, and the level of the molten metal is clearly constant. Don't be.

Since the proposal disclosed in Patent Document 2 is dedicated to a die casting machine, the use environment is limited and is not suitable for general casting or low pressure casting. In addition, since it is a transfer pipe type, it is difficult to adjust the pressure reduction, and the molten metal goes up to the vacuum device side, so that the equipment, piping, and valves are likely to be damaged.

The proposal disclosed in Patent Document 3 is merely an application of siphon action, gas sealing is not performed (not explicitly shown), and a decompression method is not clearly indicated. Therefore, oxide generation, gas entrainment may occur, or their reduction is limited. When decompressing the piping, the same problem as the problem relating to the decompression of the above-mentioned Patent Document 2 may occur. When depressurizing the inside of the holding furnace, there is a problem that the transfer distance is limited, and when the distance is long, the transfer takes time as in the case of Patent Document 1.

In common with Patent Documents 1 to 3, even if the hot water level on the side to be transferred cannot be made constant (not explicitly shown), even if an inert gas seal is performed in the transfer destination furnace When there is a possibility of inclusion formation or when an inert gas seal is performed in the transfer destination furnace, there is a problem that the gas consumption increases and the operation cost increases.

The present invention has been made in view of the above-described problems in the prior art, and can prevent oxidation and gas absorption of the molten metal during transfer, maintain at least cleanliness, An object of the present invention is to provide a molten metal transfer means that can prevent contamination and does not limit the transfer source and transfer destination.

In order to achieve the above object, a molten metal transfer pump according to the present invention is a pump for transferring molten metal by a siphon action, and includes a chamber chamber having a predetermined space, a suction tube and a discharge tube communicating with the chamber chamber, and a chamber chamber. There is a feature in that it has a pressure reducing means for reducing the pressure and a connection port opening / closing means provided at a connection port with the chamber of the discharge pipe.

In the molten metal transfer pump according to the present invention, the chamber chamber is preferably provided with a hot water level meter and an inert gas sealing means. The connection port opening / closing means includes a valve seat provided at the connection port between the discharge pipe and the chamber, a valve body seated on the valve seat, and a vertical stroke that allows the valve body to continuously contact and separate from the valve seat. An embodiment having a valve stem provided with means can be used. In this aspect, it is preferable that the valve stem is provided with a rotating means that allows the valve body to slide in close contact with the valve seat.

In addition, according to the present invention, one or more melting furnaces that melt or melt a metal to obtain a molten metal, and one or more holding furnaces that are installed at a lower position than the melting furnace and that pour the molten metal into a casting mold, , A molten metal transfer device provided at least between one and a plurality of relay furnaces installed and sealed at an intermediate position between the melting furnace and the holding furnace, and sucking the molten metal from the relay furnace and discharging it to the holding furnace 1 There is provided a molten metal transfer device including a plurality of the above-described molten metal transfer pumps.

In the molten metal transfer apparatus according to the present invention, either or both of the holding furnace and the relay furnace are preferably provided with a hot water level gauge, and preferably provided with a sealing means with an inert gas.

Furthermore, according to the present invention, there is provided a method for transferring molten metal by siphon action from one furnace storing molten metal to another furnace installed lower than the one furnace. A first step of communicating the furnace with a suction tube, a chamber chamber communicating with the suction tube, and a discharge tube communicating with the chamber chamber; and a discharge tube and a chamber chamber disposed on the other furnace side The second step of closing the connection port and depressurizing the chamber chamber and sucking the molten metal into the chamber chamber from the suction tube in which the tube port is immersed in the molten metal of one furnace, and the molten metal sucked into the chamber chamber to a predetermined amount A third step of opening the connection port between the discharge pipe and the chamber chamber after reaching the discharge chamber and discharging the molten metal to another furnace; and the chamber chamber after the discharge pipe port is immersed in the molten metal discharged to the other furnace. The decompression of the chamber is stopped, the predetermined pressure is maintained, and the inert gas is While sealing blowing, melt transfer method characterized by having a a fourth step of continuing the transport of the molten metal to another furnace via a chamber chamber from one furnace is provided.

In the molten metal transfer method according to the present invention, the opening area of the connection port between the discharge pipe and the chamber chamber is determined so that the molten metal level of another furnace as a transfer destination is detected and the molten metal level is within a predetermined range. It is preferable to change the flow rate of the molten metal. This is because the oxidation of the molten metal in other furnaces can be prevented. Alternatively, the amount of inert gas used can be reduced when sealing with an inert gas in another furnace. Furthermore, the turbulent flow of the molten metal is prevented by this flow rate adjustment. The connection port is normally fully closed in the second step of sucking the molten metal into the chamber, and half open in the third step of discharging the molten metal to another furnace, and is fully opened when the molten metal level in the chamber rises. The

When the molten metal transfer pump according to the present invention is used, the suction pipe is connected to the transfer source, the discharge pipe is connected to the transfer destination, the transfer source and the transfer destination are connected, and the chamber chamber is depressurized and transferred by the decompression means. After the molten metal is sucked into the chamber chamber from the beginning, the molten metal is discharged to the transfer destination, and if the transfer source and the transfer destination are connected by the molten metal and kept under a certain pressure (negative pressure), the transfer of the molten metal is achieved by siphon action. continue.

The melt transfer pump according to the present invention is independent from the transfer source and the transfer destination, is excellent in versatility, and can be applied as a melt transfer means without limiting the casting method.

For example, when the transfer destination is a holding furnace of a low-pressure casting apparatus, the molten metal can be transferred to the holding furnace independently of the pouring from the holding furnace to the mold. Accordingly, the production efficiency is further improved. In addition, it is difficult for the inclusions to be generated due to oxidation of the molten metal, and casting defects are less likely to occur even when the molten metal is poured from the holding furnace to the mold during the molten metal transfer. In addition, since the hot water level at the transfer destination can be made constant, the amount of the inert gas used can be significantly reduced when sealing with an inert gas at the transfer destination, and the operating cost can be reduced.

This molten metal transfer pump (chamber chamber) can be installed in the vicinity of the transfer source furnace, etc., and the molten metal can be easily sucked into the chamber chamber via a suction pipe connected to the transfer source. Even when the distance to the tip is long, it does not take time to guide the siphon action, the molten metal can be transferred in a shorter time, and less energy consumption is required for decompression, making the decompression device smaller. Can be

The molten metal transfer pump according to the present invention uses a chamber chamber that has a predetermined space and is provided with a hot water surface meter without communicating the transfer source and the transfer destination with a pipe alone, and this chamber chamber is decompressed to induce a siphon action. Therefore, adjustment required for decompression is easy, and it is difficult to cause trouble in piping, valves, decompression devices, and the like.

Further, when used for a long time, molten metal (including oxides) may accumulate in the valve body or the valve seat, but preferably has the connection port opening / closing means of the above aspect. This can be removed every time the molten metal is transferred.

The basic form of the molten metal transfer device according to the present invention is a device in which one melting furnace, a relay furnace, a molten metal transfer pump, and a holding furnace are provided. It is possible to prevent the operation from being stopped when trouble occurs in each device, and it is possible to perform regular maintenance while the operation is continued.

Emptying can be prevented if there is a level gauge in the relay furnace that is the transfer source in the molten metal transfer pump, and overflow of the holding furnace can be prevented if there is a level gauge in the holding furnace that is the transfer destination. If both furnaces are equipped with a hot water level meter, a control device can be added to perform automatic transfer operation according to the hot water level. In addition, by monitoring the level of each furnace with a hot water level meter, it is possible to detect an abnormal operation at an early stage and prevent troubles leading to operation stoppage. Since the molten metal transfer pump has a sealing means with inert gas, if both furnaces are equipped with a sealing means with inert gas, oxidation and gas absorption of the molten metal during transfer can be completely prevented, and the molten metal quality is kept good. Therefore, characteristics such as mechanical strength of the cast product are improved.

Hereinafter, embodiments of the molten metal transfer pump and the molten metal transfer method of the present invention will be described in more detail with reference to the drawings as appropriate. Note that the present invention is not construed as being limited thereto, and various changes, modifications, and improvements can be made based on the knowledge of those skilled in the art without departing from the scope of the present invention.

First, the molten metal transfer pump will be described. The molten metal transfer pump according to the present invention is a pump using a siphon action, and includes at least (1) a chamber chamber having a predetermined space, (2) a suction pipe and a discharge pipe communicating with the chamber chamber, and (5) decompression. And (6) a connection port opening / closing means provided at the connection port between the discharge pipe and the chamber chamber. In addition, preferably, (3) a hot water meter provided in the chamber chamber, and (4) an inert gas. It has a sealing means.

(1) The chamber room has a space that is provided with a hot water level gauge, sealing means, pressure reducing means, and connection port opening / closing means, and the space stays until the molten metal that has entered from the suction pipe is discharged to the discharge pipe. pass. The space shape is not limited. The chamber chamber is formed of a material having heat resistance because at least the lower portion of the chamber chamber is in contact with the molten metal and the atmosphere becomes high temperature. Alternatively, an embodiment may be adopted in which a space is formed with an iron plate, a steel frame, or the like, and at least a portion in contact with the molten metal (such as a chamber interior surface) is coated with a heat resistant material. The size of the chamber chamber space is not limited. It is determined by the transfer capacity (maximum flow rate) and the residence time at that time.

(2) The suction pipe and the discharge pipe are pipes that connect the transfer source and the molten metal transfer pump, and the molten metal transfer pump and the transfer destination in order to make the molten metal transfer pump function. The pipe shape, pipe diameter, length, etc. are determined and not limited by the circumstances (distance to position, shape, etc.) of the transfer source and transfer destination. The molten metal transfer pump according to the present invention uses a siphon action to transfer from a high place to a low place. Thick (less pressure loss) and longer and thinner discharge tube. The discharge pipe may have a tapered shape that extends toward the transfer destination direction at least in the molten metal transfer pump (that is, in the vicinity of a valve seat described later). In this way, clogging of the molten metal is less likely to occur. The tube shapes of the suction tube and the discharge tube are preferably circular in cross section for reasons such as reducing pressure loss and preventing accumulation. The suction pipe and the discharge pipe are made of a heat-resistant material because the molten metal and the entire inner surface are in contact with each other. Alternatively, a metal tube or the like may be used to coat the inner surface in contact with the molten metal with a heat resistant material.

(3) The hot water level meter is a meter that measures the level of molten metal (water level) that stays and passes through the chamber. The hot water level meter is not limited in its principle, type, installation method and the like as long as it can be applied in a chamber chamber that becomes high temperature. For example, a floating type water level meter described later as a contact type, and a laser sensor type water level meter as a non-contact type can be given. It is preferable that the hot water level meter can output the hot water level to the outside by an electric signal, an air signal or the like. This is because it is possible to detect and notify the abnormality of the pump based on the level of the molten metal and to automate the molten metal transfer operation (starting up the pump, continuing the transfer by the siphon action, stopping the pump, etc.) described later. Moreover, it is preferable to install the hot water meter separately into a normal hot water meter and an emergency hot water meter.

(4) The sealing means is a means for sealing the chamber chamber with an inert gas and blocking molten metal that has entered the chamber chamber from air or the like. As long as the inert gas can be blown into / stopped from at least the chamber chamber, the specific contents of the means are not limited. Examples are given below. Nitrogen (N ₂ ), argon (Ar), or the like can be used as the inert gas. The purity of the inert gas is preferably as high as possible, and is preferably 99.9% or more. Inert gas can be installed independently or shared with other equipment to provide an inert gas production / purification device, be purchased in a cylinder, or have a tank to store the inert gas purchased. Then, it may be supplied through piping or the like. Blowing / stopping the inert gas can be performed by providing a valve, preferably an automatic valve. More preferably, a secondary pressure adjusting mechanism (valve) is provided in the supply system (pipe, etc.) to automatically adjust the pressure in the chamber. This is because it can save labor and reduce the consumption of inert gas.

(5) The decompression means is means for immersing the suction tube in the molten metal at the transfer source and depressurizing the other sealed chamber chamber, and sucking the molten metal from the transfer source to the chamber chamber via the suction tube. As long as the chamber chamber can be decompressed and the decompressed state can be maintained, the specific contents of the decompressor and the like are not limited. For example, a vacuum generator, a vacuum pump, or the like can be provided independently or shared with other equipment, and the chamber chamber can be sucked and decompressed through piping or the like. The capacity of the decompression means (minimum pressure, decompression speed, etc.) is not limited. The decompression state is maintained after decompression and after the molten metal reaches a predetermined level in the chamber chamber (at this time, the suction pipe is immersed in the molten metal at the transfer source, and the discharge pipe is immersed in the molten metal at the transfer destination. ), And can be realized by sealing the chamber with a valve, preferably an automatic valve.

(6) The connection port opening / closing means is provided at the connection port between the discharge pipe and the chamber. By providing the connection port opening / closing means at the connection port, the sealing of the chamber chamber required for the decompression is realized by setting the flow rate to 0 (fully closing the connection port). A simpler configuration. Specific preferred embodiments of the connection port opening / closing means will be described later.

1 and 2 show an embodiment of a molten metal transfer pump according to the present invention. FIG. 1 is a cross-sectional view of a chamber chamber of a molten metal transfer pump and connection port opening / closing means attached to the chamber chamber. FIG. 2 is a flow diagram including a molten metal transfer pump, a transfer source (for example, a relay furnace), and a transfer destination (for example, a holding furnace). The transfer destination shows a cross-section, and the molten metal transfer pump is simplified relative to FIG.

The molten metal transfer pump 1 includes a chamber chamber 2 that forms a space 21 with a fire-resistant wall, a suction pipe 4 that communicates with the chamber chamber 2, a valve seat 10 that communicates with the chamber chamber 2 and is connected to the chamber chamber 2. And a discharge pipe 3 formed. The chamber chamber 2 includes a hot water level gauge 8 (LI: Level Indicator in FIG. 2), a temperature sensor 7, a heater 6 (H: Heater in FIG. 2), and a pressure sensor 9 (PS: Pressure Sensor in FIG. 2). And a vertical stroke means that allows the valve body 11a to continuously contact and separate from the valve seat 10 and a rotation means that enables the valve body 11a to slide relative to the valve seat 10, together with the valve seat 10. A valve rod 11b and a valve body 11a constituting a connection port opening / closing means are provided. Further, a supply / exhaust hole 5 is formed in the chamber chamber 2 for blowing an inert gas for sealing and for depressurizing the chamber chamber 2. In addition, a confirmation window 12 that can be visually checked when the hot water level rises and an emergency hot water level meter 13 are provided.

The temperature sensor 7 plays a role of detecting the temperature in the chamber chamber 2 by, for example, a thermocouple, and is provided by being inserted into the chamber chamber 2 from the upper surface. The heater 6 serves to heat and maintain the temperature in the chamber chamber 2 and may be provided at the lower portion of the chamber chamber 2 so as to be immersed in the molten metal, but is provided on the upper surface of the chamber chamber 2 that is not in contact with the molten metal as illustrated. The molten metal adhering to the heater 6 is more preferable because it does not oxidize and become a inclusion. The pressure sensor 9 plays a role of detecting the pressure in the chamber 2.

The rotating means of the valve stem 11b is, for example, a pneumatic rotary actuator 24. The rotary actuator 24 rotates the valve rod 11b, and rotates the valve body 11a provided at the end of the rotary actuator 24 while being in contact with the valve seat 10, thereby realizing sliding. The vertical stroke means of the valve stem 11b is, for example, a pneumatic cylinder 22 (for half-opening) and a cylinder 23 (for full-opening). The cylinders 22 and 23 can bring the valve body 11a into close contact with and away from the valve seat 10 by moving the valve rod 11b up and down.

A vacuum pump (VP: Vacuum Pump in FIG. 2) is connected to the air supply / exhaust hole 5 via a pipe and an automatic valve. When the chamber chamber 2 is decompressed, the automatic valve is opened to operate the vacuum pump, and the suction pipe Is sealed with the molten metal at the transfer source, and the others are sucked into the sealed chamber. When maintaining the reduced pressure after the pressure reduction, the automatic valve is closed and the vacuum pump is stopped. The piping system is preferably provided with a vacuum tank (VT: Vacuum Tank in FIG. 2).

In addition, an argon gas tank (not shown) is connected to the air supply / exhaust hole 5 through a pipe and an automatic valve. The argon gas tank is a tank in which pressurized argon gas (Ar) is stored. When sealing the molten metal that has entered the chamber chamber 2, an automatic valve is opened and argon gas is blown into the chamber chamber 2 with a secondary pressure control valve or the like. The internal pressure is kept almost constant. It is preferable to provide a buffer tank (BT: Buffer Tank in FIG. 2) in the piping system. This is because the fluctuation of the supply pressure of the argon gas becomes smaller, the pressure in the chamber chamber 2 can be easily adjusted, and the consumption amount of the argon gas is further reduced.

Next, the molten metal transfer method will be described. The molten metal transfer method according to the present invention is a method of transferring molten metal from one furnace storing molten metal to another furnace installed lower than the one furnace by siphon action. Here, referring to FIG. 2, FIG. 5 (a), FIG. 5 (b), and FIG. 5 (c), one furnace is used as a transfer furnace and the other furnace is used as a transfer destination. It will be described as a furnace. FIGS. 5 (a), 5 (b), and 5 (c) are views showing only the cross section of the chamber chamber in FIG. 2 (BT and VT are omitted), and the process of the molten metal transfer method according to the present invention. It is a figure explaining an example.

First, as shown in FIG. 2, the relay furnace 32 and the holding furnace 33 are communicated with each other by the suction pipe 4, the chamber chamber 2, and the discharge pipe 3 of the molten metal transfer pump 1 (first step). To communicate here, the inlet of the suction pipe 4 is put into the relay furnace 32 and the outlet of the discharge pipe 3 is put into the holding furnace 33 so that at least the suction pipe 4 is immersed in the molten metal 30 of the relay furnace 32. Say.

Next, as shown in FIG. 5 (a), the discharge pipe 3 and the chamber chamber 2 disposed on the holding furnace 33 side are formed by stroking the valve rod 11b downward to bring the valve body 11a into close contact with the valve seat 10. Close the connection port. At the same time, a vacuum pump connected to the air supply / exhaust hole 5 via a pipe and an automatic valve is operated after opening the automatic valve, the chamber chamber 2 is decompressed, and the suction is performed by immersing the pipe port in the molten metal 30 of the relay furnace 32. The molten metal 30 is sucked into the chamber chamber 2 from the tube 4 (second step). The pressure in the chamber 2 is detected by the pressure sensor 9 and maintained at a constant negative pressure state.

Subsequently, as shown in FIG. 5B, after the molten metal 30 sucked into the chamber chamber 2 reaches a predetermined amount, the valve rod 11 b is slightly moved upward to separate the valve body 11 a from the valve seat 10. By doing so, the connection port between the discharge pipe 3 and the chamber chamber 2 is opened halfway, and the molten metal 30 is discharged to the holding furnace 33 (third step). The amount of the molten metal 30 sucked into the chamber chamber 2 can be obtained by detecting the molten metal level of the chamber chamber 2 with the molten metal level meter 8.

Next, when the molten metal 30 accumulates in the holding furnace 33 and the pipe port of the discharge pipe 3 is immersed in the molten metal 30 of the holding furnace 33, an automatic valve for piping connected to the vacuum pump connected to the air supply / exhaust hole 5 is provided. Then, the vacuum pump is stopped, the decompression of the chamber chamber 2 is stopped, and a predetermined pressure is maintained. At the same time, an automatic valve of a pipe connected to the argon gas tank connected to the air supply / exhaust hole 5 is opened, and argon gas is blown into the chamber chamber 2 for sealing (fourth step). In this state, the relay furnace 32 and the holding furnace 33 are continuously connected by the suction pipe 4, the discharge pipe 3, and the molten metal 30 in the chamber chamber 2, and the maximum pressure therebetween is lower than the atmospheric pressure. Accordingly, a siphon action occurs, and the molten metal 30 is continuously transferred from the relay furnace 32 to the holding furnace 33 through the suction pipe 4, the chamber chamber 2, and the discharge pipe 3 (FIG. 5 (c)).

In the molten metal transfer method according to the present invention, as shown in FIG. 2, a hot water level gauge 38 (LI) is provided in the holding furnace 33 that is the transfer destination, the hot water level of the holding furnace 33 is detected, and the molten metal level is detected. Thus, the valve rod 11b is moved up and down to change the distance between the valve body 11a and the valve seat 10, and the opening area of the connection port between the discharge pipe 3 and the chamber chamber 2 is changed to change the flow rate of the molten metal 30 being transferred. It is preferable to adjust. This is because the fluctuation of the hot water level of the holding furnace 33 can be made constant or can be suppressed within a predetermined range. For example, this can be realized by passing the hot water surface level information to a separately provided control system and operating the valve stem 11b according to a command from the control system. By controlling the fluctuation of the molten metal level in the holding furnace 33 within a predetermined or predetermined range, oxidation or the like of the molten metal 30 transferred to the holding furnace 33 can be prevented or suppressed. Further, as shown in FIG. 2, in the holding furnace 33, when sealing with argon gas is performed, the amount of argon gas used can be reduced.

Next, the molten metal transfer device will be described. The molten metal transfer apparatus according to the present invention includes one or more melting furnaces that melt or melt a metal to obtain a molten metal, and one or more holding furnaces that are installed at a lower position relative to the melting furnace and pour the molten metal into a casting mold. And a molten metal transfer device provided between the two. That is, it is an apparatus related to the transfer from the apparatus for producing molten metal (melting or melting metal) to the apparatus for using molten metal (filling the mold), and is installed at least at an intermediate position between the melting furnace and the holding furnace. 1 to a plurality of relay furnaces, and one to a plurality of the above-described molten metal transfer pumps according to the present invention for sucking the molten metal from the relay furnace and discharging it to the holding furnace. The low and intermediate positions refer to the relative positional relationship in the height direction determined by whether or not the molten metal can flow by the siphon action.For example, the molten metal can flow from the melting furnace to the relay furnace by the siphon action, and the molten metal can flow from the relay furnace. It can flow into the holding furnace. The molten metal transfer pump 1, the relay furnace 32, and the holding furnace 33 shown in FIG. 2 described above correspond to an example of the constituent elements of the molten metal transfer device according to the present invention.

FIG. 3 is an elevation view showing an embodiment of the molten metal transfer device according to the present invention. The melting furnace 31 in which the metal is melted or melted to produce the molten metal is at the highest position, the holding furnace 33 for pouring into a mold (not shown) is at the lowest position, and the relay furnace 32 is positioned at the intermediate position between them. Is provided. The molten metal is transferred from the melting furnace 31 to the relay furnace 32 according to gravity, and then transferred from the relay furnace 32 to the holding furnace 33 by the siphon action by the molten metal transfer pump 1.

The relay furnace 32 is disposed, for example, in the vicinity of the melting furnace 31 so that the molten metal can be transferred from the melting furnace 31 by gravity. The holding furnace 33 may be able to transfer the molten metal from the relay furnace 32 only by gravity. However, the holding furnace 33 may be transferred only by gravity due to a failure on the plane between the holding furnace 33 and the relay furnace 32. By using the molten metal transfer pump 1, the molten metal can be transferred. Therefore, the degree of freedom of the plane layout of the factory is increased, and the layout design of more efficient equipment and the like can be performed, and the land can be effectively used.

The basic form of the molten metal transfer apparatus is an apparatus provided with one melting furnace 31, a relay furnace 32, a molten metal transfer pump 1, and a holding furnace 33, as shown in FIG. The factory layout can be prioritized for design. For example, a plurality of relay furnaces connected in series may exist between the melting furnace and the holding furnace, and a mode in which hot water is poured from the relay furnace to the mold (the holding furnace also serves as the relay furnace) is included. The relay furnace is a concept that includes a holding furnace as well as a furnace that relays molten metal. Furthermore, the relay furnace can be used as a furnace for distributing molten metal.

FIG. 4 is a system diagram showing another embodiment of the molten metal transfer apparatus according to the present invention, and includes a plurality of melting furnaces 31, relay furnaces 32, molten metal transfer pumps 1, and holding furnaces 33 as constituent elements of the molten metal transfer apparatus. A mode in which a network is formed is shown. It has three melting furnaces 31 and can transfer molten metal from one melting furnace 31 to two relay furnaces 32, using at least one of the four molten metal transfer pumps 1 from one of the relay furnaces 32. The molten metal can be transferred to the five holding furnaces 33. In the case of this aspect, in the molten metal transfer pump 1, a plurality of suction pipes and discharge pipes are provided in one chamber chamber, and the transfer source and the transfer destination can be determined by selecting the suction pipe and the discharge pipe by an automatic valve or the like. I can do it.

For example, by forming such a network, there are a plurality of molten metal paths from the melting furnace to the holding furnace, and it is possible to continue the operation without stopping even when a trouble occurs in each component. . Moreover, it is possible to carry out regular maintenance while the operation continues, which contributes to the improvement of the factory operation rate.

The molten metal transfer pump and molten metal transfer method according to the present invention have a wide application range without limiting the transfer source and transfer destination, prevent oxidation of the molten metal during transfer, gas absorption, etc., and at least cleanliness In addition to being able to maintain, it is possible to adjust the level of the hot water surface of the transfer destination to a certain or predetermined range, and to prevent contamination of the molten metal at the transfer destination. Moreover, the work conventionally performed, such as transporting and distributing the ladle containing the molten metal by a lift, becomes unnecessary, which contributes to the improvement of safety in the casting process and cost reduction by labor saving.

The molten metal transfer apparatus configured using the molten metal transfer pump according to the present invention is related to the arrangement of a melting furnace, a holding furnace, and the like in a factory, enables a more free design, and includes a network of components such as a plurality of relay furnaces. By forming the structure, it is possible to improve the maintainability and the reliability of the casting process.

It is sectional drawing which shows one Embodiment of the molten metal transfer pump which concerns on this invention. It is a figure which shows one Embodiment of the molten metal transfer pump which concerns on this invention, and is a flowchart including the transfer origin and the transfer destination. It is a flowchart which shows one Embodiment of the molten metal transfer apparatus which concerns on this invention. It is a systematic diagram which shows other embodiment of the molten metal transfer apparatus which concerns on this invention. It is a figure explaining an example of the process of the molten metal transfer method which concerns on this invention, and is sectional drawing of a chamber chamber.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Molten metal transfer pump, 2 ... Chamber chamber, 3 ... Discharge pipe, 4 ... Suction pipe, 5 ... Supply / exhaust hole, 6 ... Heater, 7 ... Temperature sensor, 8 ... Hot water level meter, 9 ... Pressure sensor, 10 ... Valve Seat, 11a ... Valve body, 11b ... Valve rod, 12 ... Confirmation window, 13 ... Emergency hot water gauge, 21 ... Space (chamber chamber), 22 ... Cylinder (half open), 23 ... Cylinder (full open), 24 ... Rotary actuator, 30 ... Molten metal, 31 ... Melting chamber, 32 ... Relay furnace, 33 ... Holding furnace, 38 ... Hot water level gauge.

Claims (9)

A pump for transferring molten metal by siphon action,
A chamber chamber having a predetermined space, a suction tube and a discharge tube communicating with the chamber chamber, a decompression unit for depressurizing the chamber chamber, a connection port opening / closing unit provided at a connection port between the discharge tube and the chamber chamber, A molten metal transfer pump characterized by comprising: The molten metal transfer pump according to claim 1, wherein the chamber chamber is provided with a hot water level meter and an inert gas sealing means. The connection port opening / closing means enables a valve seat provided at a connection port between the discharge pipe and the chamber chamber, a valve body seated on the valve seat, and the valve body to be continuously brought into and out of contact with the valve seat. The molten metal transfer pump according to claim 1, further comprising a valve rod having an up / down stroke means. The molten metal transfer pump according to claim 3, wherein the valve stem includes rotating means that allows the valve body to slide in close contact with the valve seat. Molten metal transfer provided between one or more melting furnaces that melt or melt a metal to obtain a molten metal, and one or more holding furnaces that are installed at a lower position than the melting furnace and that pour the molten metal into a casting mold. A device,
At least one or more relay furnaces installed and sealed at an intermediate position between the melting furnace and the holding furnace, and the molten metal is sucked from the relay furnace and discharged to the holding furnace. The molten metal transfer apparatus comprised from 1 thru | or several molten metal transfer pumps of description. The molten metal transfer apparatus according to claim 5, wherein a hot water level gauge is provided in one or both of the holding furnace and the relay furnace. The molten metal transfer apparatus according to claim 5 or 6, wherein a sealing means using an inert gas is provided in either or both of the holding furnace and the relay furnace. A method of transferring molten metal by siphoning from one furnace storing molten metal to another furnace installed lower than the one furnace,
A first step of communicating the one furnace and the other furnace with a suction pipe, a chamber chamber communicating with the suction pipe, and a discharge pipe communicating with the chamber chamber; and the first furnace and the other furnace disposed on the other furnace side A second step of closing the connection port between the discharge pipe and the chamber chamber and depressurizing the chamber chamber, and sucking the molten metal into the chamber chamber from the suction pipe in which the pipe port is immersed in the molten metal of the one furnace; A third step of opening a connection port between the discharge pipe and the chamber chamber after the molten metal sucked into the chamber chamber reaches a predetermined amount, and discharging the molten metal to the other furnace; After the outlet of the discharge pipe is immersed in the molten metal, the decompression of the chamber chamber is stopped to maintain a predetermined pressure, and an inert gas is blown into the chamber chamber to seal it, and from one furnace through the chamber chamber. Continue to transfer molten metal to other furnaces Melt transfer method characterized by comprising a fourth step. 9. The molten metal flow rate is adjusted by detecting the molten metal level of the other furnace and changing the opening area of the connection port between the discharge pipe and the chamber so that the molten metal level falls within a predetermined range. The molten metal transfer method described.

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