JPS60170568A - Casting method - Google Patents

Abstract

PURPOSE:To improve the collapsing property of casting molds and to improve parting of the molds by pouring a molten metal into the molds at the same instant when castings are made by using the mold train formed by using an org. binder then blasting air from a blasting means to the mold train thereby accelerating the combustion of the binder. CONSTITUTION:A molten metal is poured through a pouring port 24 to a casting mold train 13 connected with casting molds solidified by using an org. binder into a layer shape. An air feed means 16 is driven upon ending of the pouring operation to introducing air through a pipe 15 into the mold train 13. The combustion of the binder incorporated into the molds is thus accelerated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting method whose purpose is to burn and remove a caking agent used to solidify sand.

Conventionally, shell molds, which are a type of casting mold, are made by firing resin coach sand. In order to use this sand repeatedly, a recycling process is performed in which the surface of the sand grains is polished after being roasted to remove the organic binder contained in the sand after casting. After that, resin etc. are added to the sand and kneaded again. In this case, the roasting process is performed at high temperature and requires a large amount of energy, so the cost is high9. However, there are problems such as an increase in the size of the equipment for performing this roasting process. For this reason, small and medium-sized foundries currently rely on specialist collectors to carry out this roasting and recycling process. Here, if the sand after casting and demolding is of such a quality that the roasting process can be omitted, industrial costs can be reduced, and the effect is extremely large.

If necessary, it should be sufficient to perform a simple polishing of the surface of the sand grains, or to slightly polish the surface of the sand grains using a mixer before adding the resin.

Therefore, in the vertical stack or horizontal stack casting method of shell molds, the difficulty in separating the product from the molding sand after casting is due to the collapsibility of the mold, that is, the resin of the foundry sand caking material. It all depends on the degree of combustion. However, in the normal stack casting method, the supply of air into the mold is not sufficient, so the resin cannot be completely combusted and remains in a carbonized state. Therefore, there were various drawbacks such as @poor disintegration of the mold, (1) foul-smelling air, (2) requiring man-hours to reprocess the sand, and (2) high cost of sand.

This shame was made in view of these conventional drawbacks,
The structure consists of a mold row in which molds solidified using an organic binder are connected in a layered manner, and an air supply means is connected. After pouring the metal from the pouring hole provided in the mold row, air is sent to the mold row. This method is characterized by blowing air from the means to promote combustion of the caking material contained in the mold. Therefore, the caking agent contained in the sand after demolding can be easily released from the mold, and the number of steps for reprocessing the sand can be reduced.

The shell mold horizontal stack casting method, which is an embodiment of the present invention, will be explained based on the drawings. (1) is a shell mold nail type, and a vertical runner (2) is formed in the center, and each of the vertical runners is It is connected to a plurality of product cavities (3) for forming products.

(4) is a space for saving the use of sand to the extent that the strength of the fa type (1) is not deteriorated. (5) is the vertical runner (2
) is a runner installed above the vertical runner to supply molten metal. (6) is the product cavity part (3), vertical runner (2)
, penetrate the mold (1) in places other than the runner (5).
It is preferable to provide a plurality of small-diameter air supply holes arranged in parallel, and in particular, it is preferable to provide at least one air supply hole (6) in each space (4).

Next, a large number of molds (1) are connected in a layered manner, and a pair of hanging plates α00 hooked to both ends of the molds are tightened with a plurality of long bolts (A) to form a mold row α1. A wall chamber α4 communicating with all of the air supply holes (6) is provided in one of the hanging plates aη, and a pipe (
C) is provided with an air supply means α0 for supplying air by rotating a motor. In the figure, α [with] is a filter, (goods) 0υ
is a plug for closing both ends of a continuous runner. or,
2) is a ventilation pipe inserted into the air supply hole (6), and has a large number of layers of small holes (C) throughout. The molds (1) are connected horizontally in multiple layers, and the mold rows (towards ) and connect it to one end of the runner (2) to provide a spout (c). Next, when molten metal is poured from the pouring port (c), the caking material in the mold is vaporized and burned by the high heat of the molten metal.

When the pouring work is completed, the air supply means αQ is driven to supply air into the mold rows (to) through the empty chambers (L4, to the ventilation pipes), and each ventilation pipe (A) is Oxygen is supplied to the combustion of the caking material through the gaps between the caking material and the sand, further promoting the combustion of the caking material, promoting the combustion of the mold, and enhancing the effect of breaking the mold. In this case, a ventilation pipe (A) having a large number of small holes throughout is inserted inside the air supply hole (6), so the air supply hole (6) may be used during pouring or during the combustion of the caking material. The second embodiment will be explained with reference to Fig. 8, and will not collapse and close midway, and will allow sufficient air to be delivered to every corner of the mold.When casting an annular cast product, There is a medium- to large-diameter opening Q inside the mold.
In the case where the pipe αQ shown in Fig. 1 is directly connected to this opening (the opening at the other end of the mold row), without using a ventilation pipe as in the case of the first embodiment. If part 02 is closed, the mold can be formed and the caking material can be sufficiently burned to facilitate mold disassembly, as in the case described above.This embodiment is the simplest. However, there are certain restrictions on the shape of the cast product.

To explain the E8 embodiment using Fig. O9, (6) is a combustion chamber consisting of a multi-layered box made of a material that can withstand high heat, and a lid (2) that can be opened and closed at the top. At one end, there is provided a blower (2) for supplying atmospheric air into the interior to promote combustion of the caking material, and on the opposite side of the blower, there is a wall vent hole (not shown). That is, after pouring the molten metal into the horizontal stack bell-shaped row (b), close the lid (■) and drive the blower (c) to supply air into the combustion chamber (6). By completely burning the caking material, the mold can be easily disassembled.This embodiment has no restrictions on the shape of the mold, and is versatile.

As mentioned above, as a result of blowing air into the caking material to promote combustion, the loss on ignition was as follows when compared with that without blowing air.

Air flow rate: 1.0 to 1, 5m, 7m1n ψUsing the field As described above, the present invention is effective in horizontal or vertical stack casting methods, and is not limited to shell molds, but also self-hardening molds, gas molds, etc. This method can also be applied to a mold using an organic binder such as a hardening mold.

In addition, a suction means α9 is provided in the pipe αe at G in FIG.
When the molten metal is injected from the spout (c) while creating an airflow on one side toward the chamber α→ side, the high-temperature molten metal entering the runner (5) and the product cavity (3) causes ,
The binder vaporizes, generates gas, and is removed, and no back pressure is created in the product cavity (3), and the molten metal smoothly enters every corner of the mold, resulting in a slow entry speed. ,
There is no possibility that the hot water will cause poor quality. In this case, the suction means α
The air current 4 flows not only through the ventilation pipe 4 in the air supply hole (6) but also between the sand grains forming the mold.

The combustible gas and bad odor contained in the gas sucked into the pipe (c) by this suction means α4 are combusted by the combustion means (1), which removes the bad odor and burns harmful substances. The gas emitted from the wood does not harm the workers, and it also removes bad odors, improving the working environment.In this way, the suction and combustion means are activated when pouring is completed. If the caking material is then combusted by forcibly supplying air with the air supply means (113), the casting work can be carried out even more smoothly and the product can be finished beautifully.

As described above, the present invention produces a cast product using an organic caking agent and a mold, and at the same time uses the high heat generated during one pouring process to forcibly supply air. By promoting the combustion and removal of the material, the disintegrability of the mold is improved and mold release is improved, and the roasting process can be omitted, reducing sand reprocessing time and costs. Furthermore, by burning the binder, it is possible to prevent the generation of bad odors and improve the work environment, thereby making it possible to improve the work efficiency of workers.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention: Figure %J-1 is a side view of the whole, Figure 2 is an enlarged sectional view of the mold row, Figure 8 is a front view of the mold, and Figure 4 is Figure 8. 5 is a sectional view taken along line A-A, FIG. 5 is a sectional view taken along line B-B in FIG.
8 is a perspective view of the ventilation pipe, FIG. 8 is a perspective view of the mold row in the second embodiment, and FIG. 0.1 is the mold row, (1G is the air supply means. Patent applicant: Kage←Reabuno's Gosukejin Patent Attorney-1) Kazuo Dai

Claims (1)

[Claims] Molten molds solidified using an organic binder are connected in a layered manner to form a mold row and an air blowing means. After pouring the metal through the pouring hole provided in the mold row, the mold is poured into the mold row from the blowing means. A casting method characterized by blowing air to promote combustion of the caking agent contained in the mold.