CN205096485U - Aluminum alloy gravity casting metal pattern is with compound dead head - Google Patents

Abstract

The utility model provides a compound pouring riser for an aluminum alloy gravity casting metal mold, which is in the shape of a hollow cylinder; the metal shell is hollow, filled with refractory fiber, and sealed with a cover; The inner surface of the metal shell is provided with the above-mentioned surface coating. The surface coating is not easy to crack and fall off, has high temperature resistance, heat insulation and heat preservation, can improve the utilization rate of molten aluminum, the yield of castings, and reduce energy consumption. The utility model has the advantages of high iron pouring riser strength, easy processing, easy welding and good thermal insulation performance of the refractory material pouring riser, avoiding the large size of the iron pouring riser and fast heat dissipation; the low strength of the refractory material pouring riser, The disadvantage of short life.

Description

Composite Riser for Aluminum Alloy Gravity Casting Metal Mold

technical field

The utility model relates to the field of aluminum alloy casting, in particular to a composite pouring riser for an aluminum alloy gravity casting metal mold.

Background technique

In the casting process, after the molten metal is poured into the mold, it changes from liquid cooling and solidification to solid, resulting in volume shrinkage. When the volume shrinkage cannot be replenished by molten metal, shrinkage cavities and porosity will occur in the casting after solidification, which will reduce the compactness of the casting and greatly reduce the mechanical properties of the casting. Therefore, it is necessary to control the solidification to prevent defects. . The use of risers is currently the most effective and popular process measure to control solidification and compensate shrinkage in the foundry industry.

In casting smaller size castings, the sprue and riser can be combined into a sprue riser to reduce the complexity of the mold. The traditional mold pouring riser is usually in the shape of an inverted truncated cone with a large top and a small bottom. It is made of iron material. Since the thermal conductivity of iron material is 45-60W/M·K, the heat dissipation is fast. In order to ensure the high temperature of the aluminum liquid at the pouring riser For castings, this type of riser is often relatively large in size, so the riser sometimes even exceeds the weight of the product; direct contact between molten aluminum and iron will cause a chemical reaction, which not only leads to corrosion of the riser, but also leads to a decline in the performance of the casting; For example, refractory materials such as aluminum silicate, mullite, etc. can be used for the pouring riser, although the size can be made smaller, but the service life is short due to insufficient strength.

Contents of the invention

The utility model provides a composite riser for aluminum alloy gravity casting metal molds in order to avoid the shortcomings of the above-mentioned prior art. There are refractory fibers, and a surface coating is provided on the inner surface of the metal shell that contacts the aluminum liquid. Using the heat preservation effect of the refractory fiber and the high temperature resistance and heat insulation effect of the surface coating, the sprue riser has high strength, small size and long service life.

The technical scheme that the utility model adopts is:

A composite riser for an aluminum alloy gravity casting metal mold, which is characterized in that it includes a metal shell, refractory fiber and surface coating, and is in the shape of a hollow cylinder; the metal shell is hollow and filled with refractory fiber , sealed with a cover; the surface coating is provided on the inner surface of the metal shell that contacts the aluminum liquid.

The utility model is also characterized in that:

The composition ratio of the surface coating is: borax (2-5)%, graphite powder (2-4)%, alumina powder (20-30)%, silicon oxide powder (25-30)%, high temperature Refractory cement (15-25)%, the rest is water glass.

The refractory fiber is aluminum silicate fiber or mullite fiber or alumina fiber.

The material of the metal shell is steel or cast iron, and the wall thickness is 1-10mm.

The beneficial effects of the utility model are:

1. The utility model has the advantages of high strength of iron pouring riser, easy processing, easy welding and good thermal insulation performance of refractory material pouring riser, which avoids the large size of iron pouring riser and fast heat dissipation; the strength of refractory material pouring riser Low and short lifespan.

2. The utility model has the advantages of easy manufacture, convenient use, long service life and low cost.

3. The surface coating of the utility model is not easy to crack and fall off, is resistant to high temperature and heat insulation, can improve the utilization rate of aluminum liquid, the yield of castings, and reduce energy consumption. Taking the automotive oil tank sensor oil valve product as an example, the product produced by the traditional iron riser is about 1.3-1.5 times the weight of the product, and the pass rate of the product is about 85%. After using the utility model, The weight of the pouring riser is reduced to 50-60% of the product weight, and the qualified rate of one-time casting is increased to more than 99%. The service life of pure refractory material pouring risers is generally no more than 100 pieces, but the utility model can reach more than 10,000 pieces.

Description of drawings

Figure 1 is a cross-sectional view of a composite riser for an aluminum alloy gravity casting metal mold.

Fig. 2 is a top view of Fig. 1 .

Fig. 3 is a schematic diagram of the application of the compound gating riser for the aluminum alloy gravity casting metal mold.

Labels in the figure: 1 metal shell, 2 refractory fiber, 3 surface coating, 4 cover, 5 casting metal mold, 6 aluminum alloy melt, 7 pouring spoon.

detailed description

Example 1

Referring to Fig. 1 and Fig. 2: Fig. 1 is a sectional view of a composite riser for an aluminum alloy gravity casting metal mold; Fig. 2 is a top view of Fig. 1;

A composite riser for aluminum alloy gravity casting metal molds of the utility model includes a metal shell 1, a refractory fiber 2 and a surface coating 3, and is characterized in that the shape is a hollow cylinder; the metal shell 1 It is hollow, filled with refractory fibers 2, and sealed with a cover 4; the surface coating 3 is provided on the inner surface of the metal shell 1 that contacts the aluminum liquid.

The utility model is also characterized in that:

The composition ratio of the surface coating 3 is: 4% borax, 3% graphite powder, 25% aluminum oxide powder, 28% silicon oxide powder, 22% high-temperature refractory cement, and the remainder is water glass.

The refractory fiber 2 is aluminum silicate fiber, mullite fiber or alumina fiber.

The material of the metal shell 1 is 20 steel, and the wall thickness is 5mm.

The production of a compound pouring riser for an aluminum alloy gravity casting metal mold of the utility model: the metal shell 1 is processed by No. 20 steel, the inside of the metal shell 1 is filled with refractory fiber 2, and then the cover is firmly sealed by electric welding 4. Deburring, sandblasting and degreasing are performed on the surface to be coated; each material is weighed according to the composition ratio of the surface coating 3, put into a container and stirred evenly to make a slurry that can be directly sprayed or Brushing, slurry concentration can be diluted with water to adjust. The sprayed or brushed coating can be used after drying at room temperature.

The surface coating 3 of the utility model is a high temperature resistant coating with high temperature resistance, oxidation resistance, corrosion resistance, strong adhesion and good high temperature stability. The coating effectively isolates and prevents the liquid aluminum from corroding the metal shell 1, and has better heat insulation effect.

See Fig. 3: Fig. 3 is a schematic diagram of the application of the compound gating riser for the aluminum alloy gravity casting metal mold.

A composite casting riser for an aluminum alloy gravity casting metal mold of the utility model is integrally welded on the casting metal mold 5 , and the aluminum alloy molten liquid 6 is cast into the metal mold to form by using a pouring spoon 7 .

Example 2

A kind of aluminum alloy gravity casting metal mold composite pouring riser that is made according to embodiment 1, wherein difference is:

The composition ratio of the surface coating 3 is: 2% borax, 4% graphite powder, 20% aluminum oxide powder, 30% silicon oxide powder, 25% high temperature refractory cement, and the rest is water glass.

The metal shell 1 is made of cast iron with a wall thickness of 10mm.

Example 3

A kind of aluminum alloy gravity casting metal mold composite pouring riser that is made according to embodiment 1, wherein difference is:

The composition ratio of the surface coating 3 is: 5% borax, 2% graphite powder, 30% alumina powder, 25% silicon oxide powder, 15% high-temperature refractory cement, and the rest is water glass.

The material of the metal shell 1 is 10 steel, and the wall thickness is 1mm.

Claims (3)

1. an Aluminum alloy gravity casting metals mould compound dead head, is characterized in that: comprise metal shell (1), refractory fibre (2) and face coat (3), shape is hollow barrel-type; Described metal shell (1) is hollow, is filled with refractory fibre (2), seals with capping (4); Described face coat (3) is provided with at metal shell (1) inner surface of contact aluminium liquid.

2. a kind of Aluminum alloy gravity casting metals mould compound dead head according to claim 1, is characterized in that: described refractory fibre (2) is alumina silicate fibre or mullite fiber or alumina fibre.

3. a kind of Aluminum alloy gravity casting metals mould compound dead head according to claim 1 and 2, is characterized in that: the material of described metal shell (1) is steel or cast iron, and wall thickness is 1-10mm.