Australian firm Ritemp Technologies Pty. Ltd. introduced a way to cool a mold efficiently and uniformly by creating a vacuum, so the cooling water can boil at very low temperatures.
The heat is transferred directly to the water, and the boiling water cools the mold. The water will always boil where it is hottest and condense where it is coolest — so the temperature profile throughout the mold gets evened out automatically. There are minimal variations in temperature across the mold surfaces.
The vapor rises to the top of the mold, where it is condensed by simple heat exchangers.
Ritemp, based in Edwardstown, claims its licensees have cut cycle time by 20-50 percent. The firm said that maintaining efficient, uniform control of mold surface temperatures during mold cooling is a major challenge facing the plastics industry.
When water boils at very low temperatures, the water can absorb heat at an enormous rate. Since it is only necessary for water to contact the target surface for this to happen, there is no need for high-velocity, forced-flow water circuits.
Most areas of the mold can be accessed by the coolant, regardless of mold complexity. Ritemp officials said multiple circuits are not normally needed, but they are easy to balance if they are required.
Tel. 61-88-374-463, fax 61-88- 299-0892, e-mail [email protected]