JPS5886966A - Casting method by forced cooling - Google Patents

Abstract

PURPOSE:To produce castings of high quality with good efficiency by inserting pipe members and accelerating the solidification of molten metal by supply of cooling media into the pipe members thereby reducing a casting cycle time and allowing the moten metal to solidify directionally. CONSTITUTION:Pipe members 9 are placed on pedestals 8, and sealing members 10 are mounted thereto, then molds are clamped. Molten metal is poured through a sprue 5, and after the completion of the pouring, the members 9 are inserted in the molten metal poured into casting cavities 4. If cooling media such as water are supplied into the members 9, the molten metal is powerfully cooled and solidification progresses from the molten metal existing in the positions near the members 9. Thus the solidification of the molten metal is extremely accelerated and the molten metal solidifies by having directivity toward the direction farther from the members 9. Thus the casting of high quality free from cavity defects is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting method, and more particularly to a casting method for efficiently casting high-quality cast products by cooling 1 m in a short cycle time.

In order to produce reliable aluminum alloy castings and the like that are free from cavities and the like, it is preferable that the S lagoon be solidified quickly and that the molten metal be directionally solidified. Conventionally, mainly in gravity casting methods and low pressure casting methods, solidification of molten metal has been promoted by cooling the mold with water or air. However, in this case, it is necessary to control the mold temperature relatively strictly to avoid overcooling of the mold and causing problems with lag during pouring. The mold control system requires relatively advanced control technology. Furthermore, since a cooling mechanism is incorporated into the mold, the mold structure becomes complicated and mold costs rise.

Furthermore, in order to eliminate casting defects, the installation location, shape, capacity, etc. of the compressor are selected and set empirically in order to perform directional solidification. However, due to the shape constraints of the casting, there are limits to the installation location, shape, and capacity of the riser, and it is often impossible to achieve good directional solidification using the riser alone.

In addition, the solidification of molten metal is controlled by using a tracing mold and selecting and setting its type and coating thickness, but in this case, the heat generated between the WIm and the mold through the coating process is It is very difficult to reliably control the solidification of molten metal due to the heat transfer.

The present invention allows the molten metal injected into the casting cavity to be partially cooled by a cooling medium, thereby speeding up the solidification of the molten metal, simultaneously shortening the casting cycle time, and achieving ideal six-directional solidification. The aim is to provide a new and improved casting method.

According to the present invention, a pipe member is arranged in the casting cavity of the mold, and the sm injected into the casting cavity is
This is achieved by a forced cooling casting method in which the pipe member is cast and a cooling medium is supplied to the pipe member to promote solidification of the molten metal.

According to the casting method of the present invention, the above-mentioned desired objectives are coupled, a cast product with excellent mechanical properties can be obtained, and solidification of molten metal can be promoted in sand casting, so that it can be used. Even if the mold used is a sand mold, a cast product of one quality can be produced.

Further, according to the casting method according to the present invention, since the mold is not directly cooled, the mold is not overcooled, and since the mold is at a low portion, no II perforation defects or cavity defects occur.

The invention will now be described in detail by way of example embodiments with reference to the accompanying drawings.

1 to 13 show one embodiment of a casting apparatus used for carrying out the forced cooling casting method according to the present invention. In these figures, 1 indicates the lower mold, 2 the horizontal mold, and 3 the upper mold. The horizontal mold 2 supports a core 11, and the lower mold 1 and the upper mold 3 constitute a casting cavity 4.

Further, a sprue 5 and a runner 6 are formed in the upper mold 3. The upper mold 3 and the horizontal mold 2 cooperate with each other to form a press 1l17.

A pedestal 8 is formed to protrude from the bottom surface of the casting cavity 4 of the lower mold 1, and a pipe member 9 bent into a U-shape is placed on the pedestal 8. The tube member 9 is made of a metal whose melting point is higher than that of the cast metal so that it will not be melted by the cast metal. This tube member 9 extends outside the mold at its end, and is connected at one end to a cooling medium supply device (not shown). The cooling medium supply device may be a water supply or the like when the cooling medium used is water.

Next, m111i, in which the forced cooling casting method according to the present invention is carried out using the casting apparatus configured as described above, will be explained.

First, the tube member 9 is placed on the pedestal 8 with the mold opened, and the seal member 10 is attached. After this, the mold is clamped.

Next, molten metal, that is, molten metal, is injected into the tau hole 5 using a Note I device (not shown). FIG. 2 shows the state after pouring is completed. After the pouring is completed, the pipe member 9 is cast by the *** poured into the casting cavity 4.

After the pouring of the molten metal is completed, a cooling medium such as water is supplied to the pipe member 9. The chain member 9&- is supplied with a cooling medium, and as the cooling medium moves through the chain pipe member 1, Ilm is strongly cooled, and the molten metal located closer to the pipe member 9 solidifies more. By cooling sm by the cooling medium flowing through the pipe member 9 in this manner, the solidification of the molten metal is significantly accelerated, and the molten metal solidifies directionally in the direction away from the pipe portion 119. The directional and rapid solidification of Ilm results in high quality castings free of cavity defects and at the same time shortens the casting cycle time.

Further, as in the illustrated embodiment, since the pipe member 9 is provided on the opposite side of the feeder 7 across the main part of the casting cavity, the wIIB inside the casting cavity is
Head to 17]l! Ideal directional solidification is now performed, making it possible to obtain high-quality cast products with excellent mechanical properties.

After the molten metal solidifies, that is, after the early casting is completed, the pipe member 9
The excess thickness of the cast part is removed from the cast part by mechanical processing. The tube member 9 may be regenerated and reused by remelting the cast metal after cutting off the surplus portion.

4 to 16 show another embodiment of the casting apparatus used in the casting method according to the present invention. In addition, Figures 4 to 6
In the figure, the parts corresponding to Figures 1 to 3 are number 1! They are indicated by the same reference numerals as those shown in FIGS. 1 to 3. In this embodiment, a casting cavity 4 is constituted by a lower mold 1, an upper mold 3, and a core 11, and two straight pipe members 9 are provided across the excess wall portion of the casting cavity 4. ing. In addition, lower mold 1 and upper mold J! ! 3 is constructed from a sand mold, and the molds are held by metal frames 12 and 13.

Next, an experimental example of the casting method according to the present invention will be explained.

[Experimental Example 1] In Experimental Example 1, an aluminum alloy having a material equivalent to JISNA grade AC-4B was cast using a casting machine as shown in FIGS. 1 and 2. In this experimental example, casting was performed using the same conventional casting method without supplying a cooling medium to the pipe member, and 1! Water at a temperature of 25°C is poured into a pipe member with a diameter of 8II at 5°C per minute.
4. Casting carried out according to the casting method according to the present invention by supplying
A pipe member with a pipe diameter of 15° is used, and the water temperature is 25°C in the pipe member.
Casting was carried out according to the casting method of the present invention by supplying water at a rate of 30 J/min.

The experimental results in this experimental example are shown in Table 1.

Table 1 In III, A indicates a part of the central face part of the casting body, and B indicates a part of the central crest part of the casting body. The solidification time shows an opening at the end of the binary eutectic crystal, and the tensile strength shows the strength test results after heat treatment T6 of part A.

[Experimental Example 2] In this Experimental Example 2, an aluminum alloy having a material equivalent to JI8 [rated AC-48] was cast using the casting apparatus shown in Figs. 3 and 4 in the same manner as in Experimental Example 1 described above. I went to

The experimental results in this experimental example are shown in Table 2.

Table 2 In Table 2, A, B, coagulation time, and tensile strength are the same as in Table 1.

The pipe member to which the cooling medium is supplied may be provided at a location where it is desired to avoid rapid solidification of the molten metal, and the closer the pipe member is provided to the casting body, the higher the cooling effect will be. If there is no problem with forming a hollow part by the tube member in the casting body, the tube member may be arranged in the casting body portion of the casting cavity. In this case, the tube part is cast into a cast product.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to these embodiments, and it is understood that various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one embodiment of a casting apparatus suitable for carrying out the casting method according to the present invention, FIG. 2 is a longitudinal section l1rj4 of the casting apparatus shown in FIG. 1, and FIG. 4 is a cross-sectional view of the casting apparatus shown in the figure, FIG.
5 is a longitudinal cross-sectional view of the casting apparatus shown in FIG. 4, and FIG. 6 is a cross-sectional view of the casting apparatus shown in FIG. 4. 1...lower type, 2...horizontal type, 3...upper type, 4...
Casting cavity, 5... Thickness 0.6... Runway, 7...
- Risser, 8... Pedestal, 9... Pipe member, 10... Seal member, 11... Core. 12.13...Gold frame patent issuer Toyota Motor Corporation representative
Patent Attorney Takeshi Akaishi (voluntary) Procedural amendment - May 11, 1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case Patent Application No. 184728, 1982
, Name of the invention Forced cooling casting method 3, Relationship with the case of the person making the amendment Patent applicant address 1 Toyota-cho, Soda City, Aichi Prefecture Name (3)
2G) Toyota Motor Corporation Representative Toshio Morita 4, Agent Address 104 Hone 1-5-19 Shinkawa, Chuo-ku, Tokyo 31II Nagaoka Pill, Kayaba-cho Telephone 551-4171 (1)
) Specifications - Correct "r*ri-type" on page 2, line 14 to r-bite j. (2) In the specification, page 3, lines 16 to 17, ``because there is no supercooling and the mold is at a low temperature'' is corrected to ``because there is no supercooling''. (3) Clarity - The rw member 9 on page 4, lines 12 to 14 is made of cast metal. ” to be deleted. (4) Add the following sentences to the lines 2 and 3 of page 7 of the specification. 7 to 9 show another embodiment of the casting apparatus used in the casting method according to the present invention. In addition, in FIG. 7 to FIG. 9, the parts corresponding to FIG. 4 to FIG.
Figure flies are indicated by the same reference numerals as those given in FIG. In such an embodiment, a tube member 9 is provided across the casting body of the casting cavity, the tube member 9 is cast within the casting body, and the inner hook portion thereof is used as a tightening bolt passage hole. be done. The tube member 9 is inserted into a positioning hole 15 provided in a hole 1114 that supports the lower mold 1 and is positioned. During the casting process, a cooling fluid such as water is supplied into the tube member 9. That cold! IIIE body supply starts before pouring,
WIm can be done either during pouring or immediately after pouring, but the earlier the time is as long as it does not cause molding problems.
The effect of rapid solidification is large. By providing the tube member 9 in the casting body, the casting body solidifies uniformly and quickly throughout the casting, thereby improving the quality and mechanical properties of the casting, and making variations between these parts extremely small. Become. Since the cast core tube member is used as part of a single product, one processing step such as drilling can be omitted. ” (5) “And Figure 2” in Section 7, Line 6 of the Specification
Correct it as r to j in Figure 3. (6) In the 1st and 2nd lines of Table 1 of Table 8 of the Specification, "a portion of the central cross-section" is corrected to "a portion of the lower part of the central cross-section." (7) "Part of the central cross section" in the second to third lines of Table 1 on page 8 of the specification; ``Plane 3 and 4''
4 to 6”. (9) Add the following sentence between the 4th and 3rd lines from the bottom of page 9 of the specification. ``[Experimental Example 3] Experimental Example 3 was conducted by casting a mold as shown in FIGS. 7 to 9. Casting of an aluminum alloy of material equivalent to JIS II grade AC-4B was carried out in the same manner as in the above-mentioned experimental example using No. 1 equipment. In this experimental example, a tube member with a tube diameter of 1211 mm was used. The experimental results in this experimental example are shown in Table 3. i! 1 [3] (10) Mincho - Page 10, line 11, "Cross sectional view" is arrogantly ", Figure 7 shows a casting @ suitable for carrying out the casting method according to the present invention.
FIG. 8 is a longitudinal sectional view of the casting device shown in FIG. 7, and FIG. 9 is a plan view showing another embodiment of the casting device. Enter the casting device transverse 1i1i1J shown in H. (11) Add the following sentence after "gold frame" on line 1011N15 of the specification. 1.14... Surface plate, 15... Positioning hole J (12)
Add Figures 7, 8, and 9.

Claims (1)

[Claims] A pipe member is placed in the casting cavity of the mold, and the molten WIG injected into the casting cavity: from above! Casting the parts, as mentioned above! A forced cooling casting method characterized by supplying a cooling medium to the member to promote solidification of the wIm.