To provide a system device integrating a steel plate part with a mated part by supplying the mated part, while adapting it to a plurality of kinds of molding parts delivered from a part molding device.

This system device is constituted of: a part molding die device 5 which delivers the plurality kinds of molding parts 1A, 1B; detecting devices 16A, 16B which detect the kinds of the molding parts 1A, 1B to generate identification signals; a selective supply device 8 which selects and supplies the mated parts 7A, 7B adapted to the predetermined molding parts 1A, 1B by the identification signals from the detecting devices 16A, 16B; and an integrating process device 6 which integrates the mated parts 7A, 7B from the selective supply device 8 with the molding parts 1A, 1B.