The cast steel cast structure Lifting apparatus. Lifting apparatus according to an embodiment of the present invention so as to be movable towards the cutting device, and a cast front with a cutter wheel for cutting the slab in the lateral direction in the cast front with a predetermined distance spaced apart position carried by the transport roller installation is, the polishing apparatus has a polishing roller for polishing the cast front, is disposed so as to be movable towards the cast grinding the front, ultrasound applying ultrasonic waves for the cast polished surface, detect the reflected echo ultrasonic receiving the measurement information from the device and an ultrasonic device comprises a main display device for outputting the convenience cast structure.