What are the classification of investment precision casting

What is the classification of precision casting? What is the classification of precision casting?

Precision casting is a general term for the process of obtaining castings with precise dimensions. Compared with the traditional sand casting process, the casting specifications obtained by precision casting are more accurate and the surface finish is better. It includes: investment casting, ceramic casting, metal casting, pressure casting and lost foam casting. So, Dalian precision casting. What are the classification of precision casting?

What are the classification of precision casting?

1. Ceramic casting

A casting method in which ceramic slurry is used to make molds for the production of castings. Ceramic slurry is made of ethyl silicate hydrolysate and pure, heat-stable refractory fine sand such as fused quartz, zirconia, steel jade and so on. In order to gel the ceramic slurry in a short time, calcium hydroxide or magnesium oxide is generally added as a catalyst. Because the composition and appearance of commonly used refractory materials are similar to ceramics, they are called ceramic type. Ceramic mold casting is a new technology developed under the premise of ordinary sand mold casting. There are two types of ceramic types:(1) Ceramic types are all ceramic slurries. The production process is as follows: firstly, the model is fixed on the template and encapsulated in the sand box, then the prepared ceramic slurry is poured into the sand box, the mold is formed after the suspected glue is hardened, and the mold is baked at high temperature. (2) Select the shaft sleeve, pour the ceramic slurry into the gap between the shaft sleeve and the model, and cast it. Can be lined with sand or metal type. Castings can reach more than ten tons. Mainly used for casting large thick-walled precision castings and single-piece small batch stamping dies, forging dies, injection molds, metal molds, die-casting molds, glass molds and other molds. The use cycle of ceramic casting molds is very similar to that of machined molds, and the manufacturing cost is also lower than that of machined molds.

2. Coated sand casting process

In the total output value of castings, 60 to 70% of the castings are produced by sand molds, of which 70% are produced by clay sand molds. The main reason is that sand casting has lower cost than other casting methods, the production process is more convenient, and the production time is short. Therefore, the automobile engine cylinder block, cylinder head, crankshaft and other castings are produced by clay wet sand process. Generally speaking, for large and medium-sized castings, iron castings can be produced with resin self-hardening sand molds, and steel castings can be produced with water glass sand molds, so that castings with precise specifications and smooth surfaces can be obtained, but the cost is higher. Naturally, the accuracy, surface finish, material density, alloy composition and mechanical properties of castings produced by sand casting are generally poor. Therefore, when these characteristics of castings are highly required, other casting methods should be used, such as investment casting (lost wax), die casting, low pressure casting, etc.

Precision casting. What is the basic concept of precision casting?

Investment casting process, ceramic casting, metal casting, pressure casting and lost foam casting. Among them, investment casting is common, also known as lost wax casting. Apply suitable embedding materials (such as paraffin wax) for embedding; repeatedly pre-impregnate refractory coating and spray fireproof sand on the investment mold, harden the mold shell and dry stirring process; melt the above-mentioned internal investment mold to obtain the cavity; bake the mold shell, Obtain sufficient strength and burn off the remaining embedding materials; pour the required metal materials; condense, shelled and sand to obtain high-precision finished products. Heat treatment, cold drawing and surface treatment are carried out in accordance with commercial standards.