JPS61199549A - Strainer core - Google Patents

Abstract

PURPOSE:To prevent the deterioration of molding sand and the generation of slag during remelting of a runner and to improve the working efficiency of casting by using a casting to mold a strainer core which has plural molten metal passage holes and is disposed to a sprue system. CONSTITUTION:The strainer core 2 made of the casting is disposed below the sprue 1 and a defectless casting without contg. foreign matter such as slag is obtd. when the melt of a spheroidal graphite cast iron is poured into a mold. The deterioration of molding sand 3 is prevented and the good reconditioned sand is obtd. without contg. the foreign matter such as porcelain and ceramics when the molding sand is recovered after shake-out. The intrusion of porcelain, etc. is obviated in the stage of remelting a runner 4 as return scrap after the shake-out. This method is thus effective for preventing the generation of slag.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a strainer core used in a sprue system of a mold into which molten metal is poured.

[Conventional technology]

Strainer cores are widely used to improve the vortex flow of molten metal poured into a mold and to prevent foreign matter such as slag from entering.

Since this strainer core is exposed to high temperature molten metal,
It is molded from heat-resistant materials such as pottery and ceramics.

[Problem that the invention seeks to solve]

When such a strainer core is used, the strainer core is crushed during demolding and mixed into the foundry sand, causing deterioration of the foundry sand. In addition, when reusing as return waste, the strainer core gets mixed into the return material and becomes a cause of frequent slag.

Recently, technology has been developed to mold graphite into rods or fibers, but these have the same disadvantages as mentioned above, and tin-plated easily meltable metal plates are also used, but the manufacturing cost increases. This is not a desirable method.

On the other hand, when casting relatively small quantities of small articles made of different materials, for example, spheroidal graphite cast iron type 2 (JIS G5
502 FCD45) casting products and spheroidal graphite cast iron products No. 3
When obtaining a cast product of type (JIS G5502 FCD50), generally a molten metal having a chemical composition of FCD45 is prepared and poured into a mold.

Next, approximately 0.1% Cu was added to the melting furnace to achieve FCD50.
The molten metal with the chemical composition is poured into a mold, and the FC
A method of obtaining a D50 casting is used.

Therefore, this is a factor that causes a rise in manufacturing costs, such as an extension of melting time and an increase in power consumption.

[Means for solving problems]

The gist of the first invention is a strainer core that has a plurality of molten metal flow holes and is formed by casting a strainer core disposed in a sprue system, and the gist of the second invention is a strainer core formed by casting. The core is a strainer core that is ultimately melted down by the molten metal injected into the mold, resulting in a chemical composition that allows the casting to match the desired chemical composition.

[Example 1] Figure 1 is a cross-sectional view of a mold, in which a cast iron strainer core 2 is disposed below a sprue 1 to prevent foreign matter such as slag from entering as a result of pouring molten spheroidal graphite cast iron. We were able to obtain a sound cast product.

After demolding, the molding sand 3 was recovered and used as recycled sand, but no foreign matter such as pottery or ceramics was mixed in, preventing deterioration of the molding sand and obtaining good quality recycled sand.

Moreover, even when the runner 4 was returned and remelted as waste after demolding, no ceramics were mixed in, which was effective in preventing the generation of slag.

[Example 2] C: 3.6%, Si: 2.6%, Mn: 0.17%
, P: 0.026%s: 0.010%, Mg: 0
．． A molten metal having a chemical composition of FCD45 of 0.53% Cu and 0.15% Cu was poured into a mold to obtain a cast product of FCD45.

Next, pour the molten metal of FCD45 into the mold to form FCD5.
A casting of 0 was obtained.

In this case, the required amount of Cu for FCD50 is 0.25%.

That is, the difference in Cu content between FCD45 and FCD50 is 0.1%. Therefore, for a mold with an injection weight of 3 kg, C.
A 150g strainer core containing 2.0% u is placed in the sprue system of the mold, molten metal of FCD45 is injected, and the strainer core is finally melted, resulting in FCD.
It was possible to obtain a cast product with an FCD of 50 using the molten metal of 45.

〔Effect of the invention〕

The strainer core of the present invention has many excellent effects described below.

1. Since the strainer core is made of cast iron, deterioration of molding sand can be prevented.

2. It is also effective in preventing the generation of slag when the runner is returned and remelted as waste.

38. By making the strainer core, which is ultimately melted by the molten metal poured into the mold, have a chemical composition that matches the desired chemical composition of the cast product, it is possible to obtain cast products of different materials using the same molten metal. .

4. Therefore, the cost reduction effect such as improvement of casting work efficiency and reduction of power consumption is significant.

5. Cast iron strainer cores can be easily installed at foundries.
Can be manufactured at low cost.

As is clear from the above description, the strainer core of the present invention brings about significant industrial effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the mold.

Claims (1)

[Scope of Claims] 1. A strainer core having a plurality of molten metal flow holes and disposed in a sprue system, which is formed by casting. 2. The strainer core according to claim 1, wherein the casting has a chemical composition that is finally melted by the molten metal poured into the mold and that allows the casting to match a desired chemical composition.