Selection of Precision Casting Methods

Selection of Precision Casting Methods

There are various casting methods, so how to determine which process method is more suitable when receiving a casting drawing? For example, if a product has a curved inner hole, we can directly make it using a mold, ceramic cores, or easily soluble cores. However, if the customer requests a high roughness inside the hole, which method would you choose to use? When using molds for bending holes, a combination core must be used to solve the problem of not being able to extract the core. Therefore, there will inevitably be parting lines, and it is necessary to solve the problem of smooth inner cavities of wax parts through mold repair; The problem of smooth inner cavity must be solved by repairing the soluble core when using it; The use of ceramic cores ensures the quality of the inner cavity through the surface of the ceramic core. Each of the three methods has its own advantages and disadvantages. How to choose? Today, precision casting manufacturer Tianyao Metal will discuss this issue in detail for everyone.

1、 Batch production of precision castings. If the batch is large, then the production method must be based on the batch. For example, in investment casting, metal molds, die casting, sand molding, etc., metal molds must be used; If the batch size is small, there must also be a mold, but it may not be a metal mold. It can be a wooden mold or other materials, but it is obvious that the service life of the mold is definitely not long.

2、 According to the dimensions of the casting. The size of castings can indirectly determine the production method of castings. General precision casting methods have their own bottlenecks. For example, in investment casting, large-sized castings will definitely not dry. One is limited by the size of the wax injection machine, while the other is limited by the slurry barrel and shell making method. Precision casting manufacturer Yufeng Metal can produce castings weighing less than 8kg.

3、 Surface roughness and dimensional accuracy. Generally, casting manuals will introduce the surface roughness and dimensional accuracy of castings produced by various casting methods. For example, investment casting and sand casting. The two indicators of the former (surface roughness and dimensional accuracy) are several levels higher than the latter. So, when the customer requests on the drawings, the corresponding casting method has already been determined.

4、 The material and structure of precision castings are also factors in determining the casting method. For example, the structure of castings is very complex, and investment casting may be given priority. Because the advantage of investment casting is that it can transform complex parts into simple parts and then combine them together without a parting surface. The material of castings, such as high-temperature alloys, is generally investment casting+vacuum furnace.

5、 The mechanical properties and metallurgical quality of castings. Strictly speaking, the mechanical properties of the castings will be indicated in the drawings of the castings or the technical agreement of the customer, and corresponding execution standards will be provided. The standards will provide corresponding performance for various casting methods, therefore, the casting method of the product can also be basically determined. For example, the performance of aluminum alloy is different when cast using two methods: metal mold and investment casting. The former is greater than the latter. For example, the metallurgical quality of metal molds is significantly better than that of investment casting.

Precision machining