FORGING DEVICE BY HOT FORGING

PROBLEM TO BE SOLVED: To provide a forging method by hot forging where a degree of freedom of a design shape is increased as compared with a conventional method, and a forged product preventing problems of mechanical strength degradation, stress corrosion cracks or the like can be manufactured inexpensively.SOLUTION: Forging by hot forging is carried out by a hot forging device 11 including: a forging device in which two or more process units 13 are detachably incorporated in the same forging machine; a plurality of heaters for heating metal molds in the respective process units 13; a plurality of thermocouples for detecting temperature of the metal molds of the respective process units 13; a non-contact type thermometer for detecting temperature of a forged product; and a metal mold temperature control device for controlling the plurality of heaters on the basis of output of the non-contact type thermometer and the plurality of thermocouples.