JPS6024258A - Casting method - Google Patents

Abstract

PURPOSE:To melt-stick thoroughly a pipe insert-cast into a casting in the stage of insert-casting of the pipe into the casting by holding the other of the cores inserted into both ends of the slightly shorter pipe into the core print parts between the parting planes of a cope and a drag. CONSTITUTION:Bar-shaped shell cores 8 are fitted at one end into both ends of a pipe 5 having the length shorter than the distance between the end faces 7 and 7 of a casting and are held on the other end as core prints 4 in the casting mold in the stage of insert-casting of the pipe into the casting. Since the pipes 5 does not arrive at the faces 7, 7, the outside surface of the pipe 5 is thoroughly embedded by the molten metal poured into the casting mold and is thus thoroughly melt-stuck. The casting after knock-out is cleaned by shot blasting, etc. Since the cores 8 have a short length, easy sand stripping from the face 7 of the casting 7 is made possible and the removal and conditioning of the cores 8 are extremely easy as well. The end faces of the pipe 5 are not exposed and therefore there is no possibility of damaging a cutting tool, deteriorating dimensional accuracy, etc. in the case of machining the face 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting method, and particularly to a casting method suitable for casting a pipe into a cast product.

When casting a pipe into a cast product, in the conventional method, both ends 6 and 6 of the pipe 5 are held on the skirting board 4 part of the parting surface 3 of the first die 1 and the lower die 2, as shown in Fig. 1. A commonly used method is to obtain a cast product by casting and cutting both ends 6.6 of the pipe 5 protruding from the cast product.

In this method, it is often experienced that when the molten metal is poured, the central part of the pipe 5 is completely welded, but the vicinity of the end face 7.7 of the cast product is not completely welded due to a drop in the temperature of the molten metal.

In addition, when it is necessary to machine the end face 7 of a cast product or when threading the end of a cast pipe, this is undesirable as it results in interrupted cutting, which causes the cutting tool to become stiff, or reduces dimensional accuracy. Incur consequences. Even if the cast pipe is completely welded, if the material of the cast product is different from the material of the pipe, it will adversely affect the dimensional accuracy of the cutting tool, so this is not a preferable method. Therefore, the present inventor has developed a new technique that allows a pipe surrounded by εh to be completely welded to a cast product.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pre-casting which can be completely welded over the entire length of the pipe cast into the casting.

Embodiments of the present invention will be described in detail below with reference to the drawings. Figure 2 is a cross-sectional view of the mold. The other side is held in the mold by a baseboard 4.

The effects of the above configuration will now be explained.

As mentioned above, the pipe 5 that is cast into the cast product does not reach the end face 7.7 of the cast product, so the entire outer surface of the pipe 5 is covered with the molten metal and completely welded by the molten metal poured into the mold. .

Also, one of the shell cores 8 is attached to both ends of the pipe 5.
The other side is held in the mold as a skirting board 4. Therefore, the pipe 5 is firmly held within the mold via the shell core 8.

The demolded cast product is cleaned by shot blasting, etc., but since the shell core is short, sand can be easily removed from the end face 7 of the cast product, and the shell core 8 can be removed and cleaned. It can also be done very easily.

Further, when machining the end face 7 of the cast product, since the cast pipe is not exposed on the end face 7, there is no risk of damage to the cutting tool or reduction in dimensional accuracy.

Furthermore, as shown in Figure 3, by increasing the diameter of the end of the shell core 8, the stability of the cast pipe can be improved, and sand can be easily removed and cleaned after mold removal. It's something you get. When the diameter of the cast pipe is large or the entire length is long, it is effective to make the core 8 hollow and to form the waste discharge holes 9 in the pipe in stages.

In Example I, shell cores were fitted into both ends of the cast pipe 5, but the invention is not limited to this.
It goes without saying that the first objective can be achieved using a ceramic core (the same can be achieved by using a ceramic core, ', 02 core, cold box core, etc.).

As is clear from the explanation below, the casting method according to the present invention completely welds the cast pipe inside the cast product, has no adverse effects during machining, and has excellent industrial effects. It has the following.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional mold, FIG. 2 is a sectional view of a mold according to the present invention, and FIG. 3 is a partial sectional view showing another embodiment. 4: Skirting board 5: Pipe 7: End face 8: Core = 4-

Claims (1)

[Claims] A casting method characterized in that, when a pipe is cast into a cast product, one of the cores is inserted into both ends of the pipe that do not reach the end face of the cast product, and the other core is held in the mold as a skirting board.