PURPOSE: To easily track and specify quality control data from products after shipping at the time of claim generation or the like by automatically preparing information for specifying respective die casting products, marking the information to the products after casting and successively and automatically gathering the quality control data corresponding to the products from the various kinds of measurement devices.

CONSTITUTION: Information gathering devices 5..., 6... and 7... are connected to die casting mechaines 1..., the various kinds of the measurement devices 2..., and 4..., and marking devices 3... and they are incorporated in a private branch LAN system 10 through cell management computers 9.... Also, a host computer 11 is connected to the private branch LAN system 10 as well and the quality control data automatically gathered by the information gathering devices 5..., 6... and 7... are successively stored in the host computer 11.