Basic concept of precision casting

It includes: investment casting, ceramic casting, metal casting, pressure casting, lost foam casting.One of the more commonly used is investment casting, also known as lost wax casting: choose suitable investment materials (such as paraffin wax) to make investment;Repeat dipping refractory coating and sand spraying on the investment mold, hardening shell and drying;Then melt the internal mold to get the cavity;Roasted shell to obtain sufficient strength, and burn the residual investment materials, pouring the required metal materials;Solidification cooling, dehulling after sand cleaning, so as to obtain high-precision finished products.According to the product needs or heat treatment and cold processing and surface treatment.

Precision casting, also known as lost wax casting, its products are precise, complex, close to the final shape of the parts, can not be processed or rarely processed directly used, so investment casting is a near net form of advanced technology.Ancient China: wang ziwu ding, copper ban, copper lion and so on, are the masterpiece of investment casting.Since investment casting was used in industrial production in the 1940s, it has been developing at a rapid speed for half a century.In particular, European and American countries are developing rapidly.At present, investment casting is used in almost all industrial sectors, especially in the sectors of electronics, petroleum, chemical industry, energy, transportation, light industry, textile, pharmacy, medical apparatus and instruments, pump and valve.In recent years, China has also developed rapidly.The development of investment casting technology enables investment casting not only to produce small castings, but also to produce large castings. The outline size of the largest investment casting is nearly 2m, while the minimum wall thickness is less than 2mm.At the same time, the investment casting is more precise, in addition to linear tolerance, parts can also achieve a higher geometric tolerance.The surface roughness of investment castings is getting smaller and smaller, up to Ra0.4 m.