processingdetails

Plaster Mold Casting

Plaster mold casting is a common casting process, which is quite similar to sand casting. the main difference between them is the material that plaster mold casting used is the plaster of Paris instead of sand Casting like sand casting and plaster mold casting are expendable mold processes, however plaster mold casting can only be used with non-ferrous materials ,that is the feature distinguish form other kind of mold casting. Plaster casting molds, as the name suggested, it is made of plaster of Paris.

The process of the plaster mold casting, the step can be mainly divided into three steps. First, the plaster is mixed and the pattern is sprayed with a thin film of parting compound to prevent the plaster from sticking to the pattern. The plaster is then poured over the pattern and the unit shaken so that the plaster fills any small features. The plaster sets, usually in about 15 minutes, and the pattern is removed. The mold is then baked, between 120 °C (248 °F) and 260 °C (500 °F), to remove any excess water. The dried mold is then assembled, preheated, and the metal poured. Finally, after the metal has solidified, the plaster is broken from the cast part. The used plaster cannot be reused.

Plaster mold casting is used for castings as small as 30 g (1 oz) to as large as 45 kg (99 lb). Generally, the form takes less than a week to prepare, after which a production rate of 1–10 units/hr-mold is achieved. Parts that are typically made by plaster casting are lock components, gears, valves, fittings, tooling, and ornaments.