PURPOSE: To rapidly cool a metallic product with which heating is completed in a short period of time by hanging the metallic product which is heated to a high temp. in a heating furnace to a transporting base and feeding the product into a cooling chamber positioned right below the heating furnace.

CONSTITUTION: Opening/closing doors 6R, 6L of the heating furnace 1 are opened and a lifting chain 11 is lowered down to a prescribed position. Both the left and right positions of the transporting base 2 hanging the metallic product W in a feeding/ejecting zone Z is guided and supported to a lifting stand 13 where the chain 11 is engaged with the front end of the transporting base 2. The chain 11 is then pulled up and the metallic product W which is held hung to the transporting base 2 is housed into the heating furnace 1. The opening/closing doors 6R, 6L are closed and the product is heated to a high temp. by a heater H. The opening/closing doors 6R, 6L are opened and the chain 11 is lowered to feed the metallic product W into the cooling liquid in the cooling chamber 3 upon completion of the heat treatment. The metallic product W is subjected to the hardening treatment in this way in an extremely short period of time by the extremely simple operation and the hardening quality is improved.