JPH0484645A - Method and apparatus for casting thin deformed body - Google Patents

Abstract

PURPOSE:To improve a casting efficiency by arranging plural pouring holes around cores formed with the peripheral edge and pouring a molten metal at the time of casting a thin edge deformed body. CONSTITUTION:At the time of casting the thin deformed body having a thin edge, such as a washbowl covered with an enamel, the upper and lower cores 4, 5 for forming a thin peripheral edge are set so that the deformed part at center part positions is higher than the peripheral edge and also the pouring holes 10, 11, 12, 16 for casting metal are set at plural positions in core periphery to execute the casting. By this method, the yield is improved and the casting product having a little cavity and a blow hole, is obtd., and after-treatment a man-hour for correcting is reduced and the casting efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for casting a thin-walled profiled body having a thin-walled peripheral edge, such as a washbowl bowl to be enameled.

[Conventional technology]

Traditionally, enameled washbasin bowls have been cast using gunmetal with good castability and a good surface condition with few cavities, using a sand mold shown in Figure 2.

As shown in the figure, this sand mold is formed by divided sand molds 2 and 3 that have ventilation holes 1 divided into upper and lower parts at multiple locations, and a core 4.5 obtained by the CO2 process is placed between them. That's what happens.

Then, a molten metal pool 6 is provided at the upper center of the mold, and the molten metal is stored in the same-temperature pool 6, and the amount of molten metal poured is adjusted by a stopper 8 from a lower molten metal installed at the highest point in the center of the mold, and casting is performed. . In order to ensure a sufficient flow of hot water to the thin rim part, a hot water rising part 9 is provided on the outside of the rim.
A method is adopted in which a relatively large cast burr is actively formed on the outer periphery of the rim of the produced casting, and burr is removed after casting.

For this reason, not only is an extra process required for deburring, but the effects of cavities and blowholes affect the rim portion of the product, which causes a deterioration in the quality of the product.

[Problem to be solved by the invention]

The problem to be solved by the present invention is to provide a method and apparatus for reducing the amount of flash generated at the edges and obtaining a casting with a small amount of occluded gas when casting a profiled body having such a thin peripheral edge. be.

[Means to solve the problem]

In the casting of a metal deformed body having a thin peripheral edge according to the present invention, the upper and lower cores forming the thin peripheral edge are arranged so that the deformed part in the center is located higher than the peripheral edge, and The above problem was solved by injecting molten metal into a mold that had an inlet for casting metal and a hot water vent with a high center part.

[Effect]

The molten metal injected from multiple sprues located around the core periphery pushes out the gas that was inside the mold as it enters the high central area, where it is forced out of the gas vent holes into the outside air. At the same time, by pushing the tip portion of the fluidized molten metal, which has a large amount of gas storage, up to the rising portion, it is possible to reduce the amount of gas storage in the cast metal.

In addition, the occurrence of blowholes and cavities can be further reduced by forming a hot water outlet with a gas vent in the runner between the pouring ports provided at multiple locations on the thin-walled periphery and multiple locations on the outer periphery of the upper and lower cores. I can do it.

〔Example〕

An example in which the present invention is applied to the casting of an enameled washbasin will be shown below.

Figure 1 shows an example of an apparatus for carrying out the method of the present invention, and the sand molds 2, 3 and C02 cores 4, 5 are arranged at the center, which corresponds to the bottom of the product, as in the case of Figure 2, which shows the conventional example. The parts are arranged on the upper side, and the central part is arranged above the outer peripheral edge.

In the present invention, a molten metal pool 10 is provided above a plurality of locations on the thin peripheral edge formed by the core 4.5, and the molten metal is poured from there through a sprue 11 and further through a runner 12 into the mold. Furthermore, a hot water rising part 14 is formed in the central high part, and has a gas venting part 13 whose upper surface is open.

Furthermore, in the case of this embodiment, a rising part 16 having a gas vent part 15 is formed between the runners 12 and the periphery of the mold formed by the cores 4 and 5.

Below, a bronze-based (type 6, BC6) alloy was cast using the casting apparatus shown in FIG.

In FIG. 1, the above alloy heated to 1200 t from a sprue 11 was cast at a ratio of 5:5.

As a result, when a washing bowl with a diameter between outer peripheral edges of 700 mm and a thickness of 5 mm at the bottom of the center was cast, a casting with extremely few cavities was obtained. The yield including final grinding was 98%.

On the other hand, in the case of the conventional example shown in FIG. 2, there were many casting cavities, and the overall yield including cutting of the outer peripheral edge was 50 to 70%.

〔Effect of the invention〕

The following effects can be achieved by the present invention.

(1) Improved yield and castings with extremely few cavities and blowholes can be obtained.

(2) The surface condition of the casting is good, and a casting product suitable for enamel can be obtained.

(3) Since there are fewer occurrences of cavities and cracks, the time required for post-processing for correction is shortened, and casting efficiency is improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an apparatus as an embodiment of the present invention. FIG. 2 is a cross-sectional view of a conventional device. 1: Ventilation hole 2, 3: Split sand mold 4.5: CO2
Core 6; Pool 7: Sprue 8: Stopper 9; Finishing part 10: Pool 11: Sprue 12: Runway 13 15: Gas venting part 14.16 + Finishing part Patent applicant: Toto Kiki Co., Ltd. Representative: Kobori profit

Claims (1)

[Scope of Claims] 1. A method for casting a thin-walled deformed body, in which molten metal is injected from the thin-walled peripheral edge into a mold in which the deformed portion of the center below the thin-walled peripheral edge is placed higher than the peripheral edge. 2. Arrange the upper and lower cores that form the thin periphery so that the deformed part at the center is located higher than the periphery, and provide casting metal inlets at multiple locations on the periphery of the core, and vent gas at a high central location. A casting device for thin-walled deformed bodies formed by forming a hot-boiling part.