PURPOSE: To heat and dry two or more workpieces which are the same in heating condition but different in heating period of time, by providing two or more holders to set the workpieces and transfer devices to bring the holders into a heating furnace.

CONSTITUTION: A workpiece 11 to be heated is set in a workpiece set basket 1 in standby, and charged and heated in a heating furnace 3 which is kept at a stable heating condition by hot-air generated by a heater 7 and a blower 8, workpiece set basket 1a is taken out of the heating furnace 3 at the set time of a timer built in a transfer cylinder control box 5 to finish heating. With a consideration given to safety, a buzzer sounds when a specified time has elapsed after the completion of heating and the basket 1a is taken out in response to the sound of the buzzer to ensure cooling after heating.