Surface temperature control system.

摘要

A thermally-insulating layer (23) is applied to the inner surface of a mold wall (10) to control the heating and cooling of the mold. Its thickness and thermal properties are chosen so that at least half the temperature drop across the mold wall is in the surface layer. To increase the thermal insulation hollow spheres (24) are included in the layer. Graphite fibres (25A) provide reinforcement against cracking due to thermal cycling. In the case shown they form a conductive mat for electrical resistance heating of the layer but the layer is also useful when the heat comes from the material introduced into the mould. A thin fibrous paper layer (26) can be included in addition.