Precision casting refers to the process of obtaining precise size castings.Compared with the traditional sand mold casting process, precision casting can obtain more accurate casting size and better surface finish.It includes: investment casting, ceramic casting, metal casting, pressure casting, lost foam casting.

Precision casting, also known as lost wax casting, its products precision, complex, close to the final shape of parts, can not be processed or rarely processed directly used, is a near net form of advanced technology.

The basic concept

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 appropriate investment materials (such as paraffin wax) to manufacture 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;Roasting the shell to obtain sufficient strength and burning off the residual investment materials;Metal materials required for pouring;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.

The process flow

Wax pressing (injection molding) ---- wax repairing ---- wax inspection -- group tree (wax module tree) ---- -- shell making (first dip pulp, pour sand, then dip pulp, and finally mold

Shell dry) - dewaxing (steam dewaxing) -- -- -- -- -- - mold shell roasting, elasticity analysis, casting (within the shell mould casting molten steel) - vibration - to moult his shell

Separation, castings and casting rod cutting grinding gate - test (MAO embryo screening) -- -- -- -- -- -- -- -- the shotblast cleaning machine -- -- -- -- -- -- -- -- polish finished product - into the Treasury

Casting production process is generally like this in general can be divided into wax, shell, pouring, post-treatment, inspection

Wax pressing includes (wax pressing, wax trimming, tree setting)

Wax press -- use wax press to make wax models

Wax -- correct the wax mold

Group tree -- group tree with wax model

Shell making including (hanging sand, hanging pulp, air drying)

Pouring includes (roasting, chemical analysis also known as playing spectrum, pouring, shaking shell, cutting gate, grinding gate)

Post-treatment includes (sand blasting, shot blasting, correction, pickling)

Inspection includes (wax inspection, initial inspection, intermediate inspection and finished product inspection)

The development of

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.Investment casting is used in almost all industrial sectors, especially electronics, petroleum, chemical industry, energy, transportation, light industry, textile, pharmaceutical, medical equipment, 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.