Foundry moulds made by freezing moist sand - where sand is cooled by liq. nitrogen or carbon di:oxide, and then sprayed onto pattern together with cold water

摘要

Cooled sand and water are simultaneously sprayed onto a foundry pattern to make the mould. The sand is pref. cooled via direct thermal contact with a coolant, and the cold sand is pref. deposited as a fine spray on the pattern via a stream of cold, pressurised gas, and a coolant is pref. also sprayed onto the sand surrounding the pattern. A coolant may also be sprayed onto the pattern. The coolants employed ared pref. liq. N2 or liq. CO2, and the water sprayed onto the pattern is pref. first cooled to near its freezing point. Provides provides a faster and less expensive method of mfg. frozen sand moulds than conventional processes.