Precision casting refers to the use of non-metallic molds

Update:10 Nov 2018
Summary:

The precision casting method refers to the general term […]

The precision casting method refers to the general term for casting methods using non-metallic molds with higher dimensional accuracy than ordinary sand mold castings, including Lost Wax Casting or Investment Casting, Plaster Mold Casting and ceramic molds. Ceramic Mold Casting.

Dewaxing precision casting

Features and Benefits

(1) The maximum limit length of the casting is 700mm, and the length of the easy casting is less than 200mm. The maximum weight of the casting is about 100 kg, usually less than 10 kg.
(2) The dimensional tolerance of castings is 20mm ± 0.13mm, 100mm ± 0.30mm, 200mm ± 0.43mm, and the dimensional accuracy of small parts is not easy to reach within ±0.10mm. The angular tolerance is ±0.5~±2.0 degrees, and the minimum thickness of the casting is 0.5~1.5mm. The surface roughness of the casting is about Rmax 4S~12S.
(3) There are no restrictions on the material of castings, such as aluminum alloy, magnesium alloy, titanium alloy, copper alloy, various steel materials, cobalt-based and nickel-based heat-resistant alloys, and hard materials.
(4) Producing a workpiece with a complicated shape, with good dimensional accuracy and less cutting work.
(5) Save material waste and mass production.

Dewaxed precision castings are widely used in jet engines, gas turbines, steam turbines, aircraft parts, internal combustion engines, vehicles, food machinery, printing machinery, paper making machinery, compressors, valve parts, pumps, measuring instruments, sewing machines, weapons, Business machines, and other machine parts.

Process

There are two main types of dewaxing casting methods: the Solid Mold method and the Ceramic Shell Mold method, the latter being the former improvement method.

The solid molding method is to prepare a mold similar to the final casting size after considering the amount of condensation shrinkage of the wax type, the amount of heat expansion of the mold, and the amount of condensation shrinkage of the molten metal. The melted wax is poured into the mold made of metal or silica gel, and after the wax type is taken out, the slurry of the micro-powder refractory and the binder is immersed. After the dipping, the coarse refractory material is spread and allowed to dry. It is placed in a casting frame, and the refractory particles mixed with the binder are filled, and then dried. Then, the wax is melted and melted by heating to form a mold. The mold is heated at a high temperature, a small amount of residual wax is burned off and its strength is increased, and then a molten metal is injected.