JPS6346225Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a zinc shot production apparatus which is optimal for use in dropping molten zinc into water to obtain zinc shots of a certain spherical shape.

Zinc shot for blasting, which is used to remove casting flash from metal surfaces, is moderately soft and can provide a blasting (abrasive) effect without damaging the material, and is relatively inexpensive. The demand is expected to increase.

Therefore, it has been desired to be able to manufacture zinc shots with a certain spherical shape. Conventionally, zinc shots have been manufactured by dropping molten zinc into water from a nozzle at a constant pressure because of its large cooling capacity and ease of use. Attempts are being made to do so. By the way, in order to obtain a shot with a constant spherical shape, it is necessary to carefully control various factors such as the temperature of the molten metal, the nozzle dimensions, the distance between the nozzle and the water surface, and the pressure applied to the molten metal. For example, as an attempt to obtain a specific spherical zinc shot, there is a manufacturing method disclosed in JP-A-58-214331. In this method, molten zinc is placed in a molten metal container that has a dripping nozzle at the bottom, and an external force is artificially and actively applied (by air pressure) from the outside to create a certain pressure on the molten metal at the nozzle opening. We are trying to obtain a zinc shot with a certain spherical shape.

However, although this method uses an air control device, the pressure inside the molten metal container fluctuates due to a decrease in the amount of molten metal, which tends to cause pressure changes in the molten metal at the nozzle opening. Not only is it difficult to obtain, but the molten metal inlet is closed during pressurization, so pressurization must be interrupted and molten metal replenished each time the molten metal decreases, making it difficult to produce high-quality zinc shot through continuous dripping. There is a problem in that productivity cannot be improved and costs cannot be reduced.

This idea was made in order to solve the above problems, namely, without using any large-scale air control equipment, the height of the molten metal surface in the molten metal container was kept constant, and a constant spherical shape was created. It is an object of the present invention to provide a zinc shot manufacturing apparatus that can produce zinc shots by continuous dropping, and that can improve the quality of zinc shots, improve productivity, and reduce costs.

Therefore, in order to achieve this purpose, the zinc shot manufacturing apparatus of this invention includes a cushion pot that prevents ripples and removes oxides from the molten zinc sent from the molten metal pot, and a cushion pot that prevents the oxidation of the molten zinc flowing from the cushion pot. A nozzle receiver that allows the overflow of the molten metal to flow outside to constantly collect the molten zinc to a set level and drips the molten zinc into water from a nozzle at the bottom, and a nozzle receiver that returns the overflow to the molten metal pot side. It is characterized by being equipped with a return gutter that keeps the height of the hot water level constant.

This invention will be explained below with reference to an illustrated embodiment.

1 and 2 are a plan view and a side sectional view showing an embodiment of the zinc shot manufacturing apparatus of this invention. 1 in the figure is a molten metal pot, which includes:
For example, molten zinc Z with a purity of 99.99% is stored, and this molten zinc Z has a temperature of, for example, 600℃ to 650℃.
The molten metal temperature is maintained at a certain temperature. Reference numeral 2 denotes a metal pump, which allows the molten zinc Z to flow in a constant amount to the cushion pot 3 of the next stage via the dipping 2a.

The cushion pot 3 has cushion walls 3a and 3b in the middle of the molten metal flow path 3c, and these cushion walls 3a and 3b are used to prevent the molten zinc metal Z from undulating and to remove oxides (slag) in the molten zinc metal Z. ). In addition, the molten metal flow path 3c
In the middle, molten zinc Z is poured from cushion pot 3.
An overflow prevention channel opening 3d for preventing overflow is provided toward the side.

A nozzle receiver 4 is provided on the main flow channel opening 3e side of the cushion pot 3. The nozzle receiver 4 includes a molten metal flow path 4a reaching the lower part of the main flow path 3e, an overflow prevention flow path 5 provided laterally from the molten metal flow path 4a, and a bottomed, substantially cylindrical molten metal reservoir. 6. This molten metal reservoir 6
As shown in FIGS. 3 and 4, a spirally wound cylindrical hot plate 7b is provided on the outer periphery of a bottomed housing inner cylinder 7a made of a corrosion-resistant and heat-resistant material.
The temperature of the molten zinc Z contained in a is set to 540 to 600℃.
It is now possible to hold the When the surface height of the molten zinc Z accommodated in the housing inner cylinder 7a exceeds the set molten metal surface height S as shown in FIG. can be emitted to the return channel 8 side.

Therefore, the surplus molten zinc Z from the overflow prevention channel opening 3d of the cushion pot 3 and the overflow prevention channel opening 5 of the nozzle receiver 4 can be returned to the molten metal pot 1 via the dipping 8a by the return gutter 8. It is.

As shown in FIGS. 3 and 4, a plurality of nozzles 9 (five in the embodiment) are provided at the bottom of the housing inner cylinder 7a of the nozzle receiver 4. As shown in FIGS. This nozzle 9 is made of ceramic such as alumina, silicon nitride, silicon carbide, etc., and each nozzle 9 has three nozzle holes 10 as shown in FIGS. 5A and 5B. The number of nozzles 9, the number and arrangement pattern of nozzle holes 10, and the nozzle diameter are appropriately determined in relation to the production speed of the zinc shot, the size of the shot, and the like. The tip diameter d and tip length l of the nozzle hole 10 are preferably set to about 0.5 mm and 0.5 mm or less to obtain a shot of about 1 mm, for example.

By the way, below the nozzle receiver 4 mentioned above, as shown in FIGS. 2 and 3, a granulation tank 11 is installed for cooling and solidifying the molten zinc Z dropped from the nozzle hole 10. . The height of the water surface of the cooling water L stored in this granulation tank 11 is always kept constant, and the distance between the water surface and the lower end of the nozzle hole 10 is set at 10 mm to prevent flattening of the shot due to drop impact. The thickness is preferably about 3 to 5 mm.
Further, the water temperature is preferably 30 to 50°C, preferably around 40°C, in order to make the shots spherical and have a particle size of, for example, around 1 mm.

Next, the operation of the above configuration will be explained. Note that the flow of the molten zinc Z is indicated by arrows in FIGS. 1 and 2.

The molten zinc Z continuously pumped out from the molten metal pot 1 by the metal pump 2 is suppressed from undulating in the molten metal flow path 3c of the cushion pot 3, and oxides are removed. The overflow portion of the molten zinc Z is quietly returned to the molten metal pot 1 side through the return channel 8 from the overflow prevention channel opening 3d. The molten zinc Z having an approximately appropriate flow rate from which the overflow has been removed is quietly poured into the molten metal reservoir 6 from the main flow path 3e through the molten metal flow path 4a of the nozzle receiver 4.

At this time, the level of the molten zinc Z in the molten metal reservoir 6 is adjusted so that the poured overflow is always quietly returned to the molten metal pot 1 side from the overflow prevention channel opening 5 through the return gutter 8. , the set hot water level height S is always maintained.

Therefore, the amount of molten zinc Z in the molten metal reservoir 6 is always constant, and from this, a constant pressure is applied to the molten zinc Z near the nozzle hole 10 of each nozzle 9, and zinc is drawn from the nozzle hole 10 at an appropriate pressure. The molten metal Z is continuously dropped into the cooling water L, and as shown in FIGS. 2 and 3, spherical zinc shots ZS having a diameter of, for example, about 1 mm are solidified.

In this way, by keeping the amount of molten zinc Z in the molten metal reservoir 6 constant, even without applying external force such as air pressure,
Appropriate pressure is applied to the molten zinc Z near the nozzle hole 10 so that it can be dripped continuously.

Note that this invention is not limited to the embodiments described above.

As explained above, according to this invention, ripples are suppressed and oxides are removed while the molten zinc metal is continuously sent from the molten metal pot to the molten metal pool, and the surface height of the molten zinc metal in the molten metal pool is set. Since the overflow (surplus) is returned to the molten metal pot side so as to maintain the surface level at all times, unlike conventional methods, there is no need to use a large-scale air control device that applies external force, and the molten zinc near the nozzle hole can be By applying appropriate pressure and continuously dropping zinc shots, it is possible to continuously produce high-quality, uniformly spherical zinc shots, which has the effect of improving productivity and reducing costs.

[Brief explanation of the drawing]

1 and 2 are a plan view and a side sectional view showing an embodiment of the zinc shot manufacturing apparatus of this invention, FIGS. 3 and 4 are a sectional view and a plan view of the nozzle receiver, and FIG. Figure A is a bottom view of the nozzle, and Figure 5B is a sectional view taken along the - line in Figure 5A. Z... Molten metal, 1... Molten metal pot, 2... Metal pump, 3... Cushion pot, 4... Nozzle receiver, 5... Overflow prevention channel opening, 6...
Molten metal reservoir, 8...Return channel, 9...Nozzle,
10... Nozzle hole, 11... Granulation tank.

Claims (1)

[Scope of utility model registration request] There is a cushion pot that prevents rippling and removes oxides from the molten zinc sent from the molten metal pot, and an overflow of the molten zinc flowing from this cushion pot is poured outside to constantly store the molten zinc up to a set level. a nozzle receiver for dripping molten zinc into water from a nozzle at the bottom, and a return device for returning the overflow to the molten metal pot side to maintain a constant height of the molten metal level in the nozzle receiver;
A zinc shot manufacturing device characterized by comprising: