Precision casting is also called investment casting

The casting precision, surface finish, material density, metallographic structure, and mechanical properties of sand castings are often poor. Therefore, when these castings require higher performance, other casting methods, such as investment (lost wax), should be used. Casting, die-casting, low-pressure casting, etc., the following is an introduction:

1. The characteristics and advantages of precision casting: precision casting is also called investment casting. Compared with other casting methods and part forming methods, investment casting has the following characteristics: 1. The casting has high dimensional accuracy, fine surface roughness, and the size of the casting The accuracy can reach 4-6 grades, and the surface roughness can reach 0.4-3.2μm, which can greatly reduce the machining allowance of castings, and realize no-surplus manufacturing and reduce production costs.

2. Castings with complex shapes and difficult to process by other methods can be cast. The outline size of the castings is as small as a few millimeters to thousands of millimeters, the thickness of the thinnest is 0.5mm, and the smallest hole diameter is less than 1.0mm.

3. Alloy materials are not restricted: materials such as carbon steel, stainless steel, alloy steel, copper alloys, aluminum alloys, high temperature alloys, titanium alloys and precious metals can all be produced by precision casting. For alloy materials that are difficult to forge, weld and cut, more It is especially suitable for precision casting production.

4. High production flexibility and adaptability. It can be used for mass production, but also suitable for small batch or even single piece production. In summary, precision casting has small investment scale, large production capacity, low production cost, and complex products The advantages of simplification of the process and quick investment results. Therefore, it is in a favorable position in the competition with other processes and production methods and has a bright future.

The inner cavity of precision castings should not use or use less cores when casting

A. To facilitate the manufacture of models, core boxes and shapes:

1) The shape of precision castings should be simple, so as to be easy to mold, and the casting parting surface should be as flat as possible and the number should be the smallest;

2) The inner cavity of precision castings should not use or use less cores when casting. When cores are used, it should be convenient to support, fix and exhaust sand. If necessary, sufficient process holes should be provided;

3) For structures such as the inner and outer sides of the precision casting and the reinforcement ribs, a certain structural inclination should be provided in the drawing direction;

4) The boss part on the precision casting should not be too different from the body of the precision casting. It is better to take the same height, and several bosses on the same surface that are close together, it is best to connect them into a whole convex part.