Investment casting shell mold manufacturing

Of investment casting mould can be divided into two entities and multilayer shell

After module dip-coating refractory coating, and refractory material shape, then through dry, hardening, so repeatedly, make the thickness of the refractory layer of the tu hung to need, thus formed a multilayer type on the module shell, usually close to the park for a period of time, make its full hardening, then fuse module, and multilayer type shell.

Multilayered shell some need packing sand filling; Some do not need, can be directly after roasting for casting.

In melting loss of casting, the shell will be affected by volume is increasing the melt die material pressure; When roasting and casting, shell each branch produce the expansion of the containment and uneven contraction, therefore, metal also high temperature chemical reactions that may occur with the shell material. So the shell has a certain performance requirements, such as small expansion rate and shrinkage; High mechanical strength, thermal shock resistance and refractoriness and chemical stability under high temperature; Shell shall also have the certain permeability, so that type of shell gas when pouring smoothly to escape. When these are linked to manufacturing shell of refractory material, binder and process.