Precision casting

Precision casting

Precision casting refers to the general term for the process of obtaining precision-sized castings. Compared with the traditional sand casting process, the size of the casting obtained by precision casting is more accurate and the surface finish is better. It includes: investment casting, ceramic casting, metal casting, pressure casting, and lost foam casting.

Precision casting is also called lost wax casting. Its product is precise, complex, and close to the final shape of the part. It can be used directly without machining or with little processing. It is an advanced process with nearly net shape.

The more commonly used is investment casting, also known as lost wax casting: using appropriate investment material (such as paraffin) to make investment patterns; repeating the application of refractory coatings and refractory sand on the investment pattern, hardening the shell and drying; Dissolve the internal melting mold to obtain a cavity; roast the mold shell to obtain sufficient strength and burn away the remaining investment material; cast the required metal materials; solidify and cool, and clear the sand after dehulling to obtain high Precision finished product. According to product needs or heat treatment and cold processing and surface treatment.

Precision casting Process flow

Pressing wax (wax mold for wax shooting) --- wax repairing ---- wax inspection ---- group tree (wax module tree) --- shell making (dip first, sand, then dip, and finally mold Shell air-drying) --- dewaxing (steam dewaxing) ------- mould shell roasting--chemical analysis--pouring (pouring molten steel in the mould shell) ---- vibration deshelling-- Casting and cutting rod cutting and separation ---- grinding gate --- preliminary inspection (hair embryo inspection) --- shot blast cleaning ----- machining ----- polishing --- finished product inspection --- Warehouse

The casting production process is generally like this. In general, it can be divided into wax pressing, shell making, pouring, post-processing, and inspection. Pressing wax includes (pressing wax, repairing wax, group tree)

Wax pressing --- using wax press to make wax molds

Repair wax --- correct the wax mold

Group tree --- group the wax mold

Shell making includes (hanging sand, hanging pulp, air-drying)

Pouring includes (roasting, chemical analysis is also called spectroscopy, pouring, vibrating shell, cutting gate, grinding gate)

Post-processing includes (sandblasting, shot blasting, correction, pickling)

Inspection includes (wax inspection, preliminary inspection, intermediate inspection, finished product inspection)

Specific applications of precision casting

Casting is the process of casting liquid metal into the cavity of a mold and waiting for it to cool and solidify to obtain the finished product. In terms of types, there are sand casting and special casting. And precision casting, which belongs to special casting, generally does not require further processing of the finished product. Therefore, the relationship between casting and precision casting is subordinate.

It can be said that the application of precision casting is very extensive. If it is specific, it is used in such industries as petrochemical, electronics, energy, light industry, textile, pharmaceutical, medical equipment, and transportation. Its specific products are various castings, such as copper castings, aluminum castings, steel castings, and copper and aluminum castings.

Precision casting is a type of casting, so, naturally, it belongs to the field of casting. And foundry, because it is an independent industry, and it has no industry planning area, it is usually attributed to the field of metallurgy or material molding.