PURPOSE: To promptly and surely insert a mambo as the separating material between piled steel plates, by arranging a horizontal square frame around the mambo dropped out of a group of mambos piled in one column and providing said frame with clamps opened and closed by means of hydraulic cylinders so as to hold the mambo.

CONSTITUTION: Struts 12 are vertically provided in central both sides of a bed 11, and vertical guide frames 2, in which a mambo 3 is piled in one column are also provided, then the lowermost membo 3 is separated one after another and dropped into a horizontal shuttling frame 4. The other side of each clamp element 7 mounted to the frame 4 is pivotally mounted to each connection part 10a, 10c, and each hydraulic cylinder 8 is telescopically operated to move each push- pull rod 9, and turn each element 7 so as to freely hold and release the mambo 3 placed in the frame 4. The frame 4 which holds the mambo 3 is moved onto piled steel plates 14, and each cylinder 8 is contracted at a prescribed position to reversely pull each push-pull rod 9 and release each element 7 thus place the mambo 3 on the steel plate 14 as the separating material.