WATER-AIR COOLING IN HEAT-TREATMENT OF LARGE PARTS

The choice of cooling medium is an important factor in the heat-treatm ent process. Oil used as a cooling medium cannot provide constant prop erties of heat-treated parts due to the instability of its physical pa rameters in long-term operation. In addition, oil is a source of eleva ted inflammability and can be harmful for people and the ambient. Oil is quite expensive and its use requires cumbersome and expensive equip ment (an oil tank, a vessel for emergency dumping, an oil-cooler, etc. ). This has stimulated a search for substitutes, among which water-air mixtures are of substantial interest. The present work describes a me thod for increasing the stability of hammer dies for hot deformation o f metals by optimizing existing heat-treatment regimes and developing new regimes and equipment that use water-air cooling.