Vacuum furnace with pressurized intensive water quench tank

Abstract

A heat treating furnace having a quenching chamber incorporated therein or associated therewith is disclosed. The heating chamber within the furnace is utilized to heat work-pieces to a desired temperature. When the heating cycle has been completed, the heating chamber and the quenching chamber are back-filled with an inert gas to a redundant pressure (over atmospheric). The work-pieces are then transferred into the quenching chamber and lowered into the intensively agitated water in the water quench tank by an elevator mechanism. High quenchant (water) agitation rates eliminate film boiling on the surface of the hot work-pieces. When the compressive stresses on the surface of the work-pieces are at a maximum and are at an optimum depth, or when the cooling recipes otherwise determine, the elevator mechanism in the quenching chamber lifts the work-pieces out of the water quench tank and into the inert gas blanket above the tank, thus interrupting the intensive quenching process. The cores of the work-pieces are then allowed to cool uniformly by conduction through their intensively quenched outer shells. After cooling, the work-pieces, having both high hardness and low distortion, are removed from the quenching chamber.

1 . Heat treating apparatus for heat treating work-pieces comprising a vacuum or low pressure gas heat treating furnace having a heating chamber, a tank containing an intensive quenching media, means for segregating said heating chamber of said heat treating furnace from said tank containing said intensive quenching media, means for agitating said intensive quenching media in said tank, means for introducing an inert gas into the heat treating apparatus, and means for immersing the work-pieces into and removing the work-pieces from said quenching media in said tank in accordance with intensive quenching methods.  
   
   
       2 . The heat treating apparatus as defined in  claim 1  wherein said inert gas introducing means introduces an inert gas at a pressure in excess of atmospheric into the area over said tank containing said intensive quenching media.  
   
   
       3 . The heat treating apparatus as defined in  claim 1  wherein said heat treating furnace is physically separate from said tank containing said tank said intensive quenching media.