PURPOSE: To decrease operation cost, improving the cooling effect of a mold by causing the water jetted from water jet nozzles to become a forcible jet stream directed to a urethane mold, feeding the water kept at a constant temperature by the pump arranged outside of a water tank.

CONSTITUTION: Pipes 5 sending under pressure the water kept at a constant temperature into a cooling water tank 3 by a pump 6 arranged outside of the cooling water tank 3, are arranged under the truck 1 conveying a mold. Many water jet nozzles 4 directed to an urethane mold 2 are provided on each pipe 5. Consequently, the water jetted to the surface of the urethane mold 2 in an arrow direction from the water jet nozzle, is caused to become a forcible jet stream, thereby improving the cooling efficiency of the urethane mold 2. The cooling time for the urethane mold is reduced, improving the cooling effect of the urethane mold by a dipping system, and simultaneously, the length of the cooling water tank may be shortened.