PURPOSE: To make it possible to perform sufficient steam cleaning by dipping such a product having been machined by use of an ultra precision lathe as an aluminium disk or the like in Freon liquid, cleaing said product by giving ultra sonic vibration to the liquid, and then spraying Freon liquid to said product intermittently during cleaning with Freon steam.

CONSTITUTION: Sprays 13 for Freon liquid are provided around an aluminium disk (a) in a steam bath 3 to spray Freon liquid with valves 12a and 12b for Freon liquid changed over. Then the Freon liquid in the steam bath 3 is made to evaporate by heater 4 to perform steam cleaning for the and spraying of Freon liquid from the spray 13 to the disk (a) alternately in the bath 3. The Freon steam in the steam bath 3 is cooled by cooling tubes 5, condensed into Freon liquid, flows down into a distillation trough, sent to a second liquid bath 1b after the separation of water in a water separation bath 7 and then flows into a first liquid bath 1a when said bath 1b overflows. The overflowed liquid is sent to the steam bath 3 and spray 3 alternately by a pump 9 through a steam bath 11 passing a water separation bath 7.