Apparatus and method for changing dies

A die changing apparatus for a plate reduction press machine having a transfer line for transferring a slab through the machine, the machine having upper and lower sliders movable in a direction of a thickness of the slab and disposed to press upper and lower dies located vertically on opposite sides of the slab onto the slab, the die changing apparatus comprising:

• upper and lower die clamps having first and second positions fixing the upper and lower dies to the upper and lower sliders, and releasing the upper and lower dies from the upper and lower sliders, respectively;
• split rails installed below a lower portion of the lower die holder having a first raised position in contact with the lower die holder and a second lowered position out of contact with the lower die holder, the split rails extending horizontally in a lateral direction of the transfer line;
• die changing rails in a continuous line with the split rails, the die changing rails having support surfaces flush with the support surfaces of the split rails when the split rails are in the first raised position, wherein the die changing rails extend outside the reduction press machine;
• a plurality of shift rails having support surfaces flush with the support surfaces of the changing rails;
• a sideways shift apparatus for moving the shift rails in a direction along the press line so that one pair of shift rails is aligned with the changing rails;
• and
• a die clamp moving apparatus moving the upper and lower die holders with the dies, after being removed from the die clamps, from the raised split rails, to the shift rails through the changing rails.

In a method of changing dies for a plate reduction press machine having a transfer line for transferring a slab through the machine, comprising the steps of:

• providing upper and lower dies arranged vertically on opposite sides of a slab;
• and providing upper and lower sliders that press the slab by an upwards and downwards, forwards and backwards motion;
• a method of changing dies for a plate reduction press machine, further comprising the steps of:
• providing upper and lower die holders for fixing the upper and lower dies, respectively;
• providing upper and lower die clamps for fixing the die holders in a detachable manner;
• providing split rails installed on a lower portion of the lower die holder, and extending horizontally in the lateral direction of the transfer line, the split rails having a first raised position in contact with the lower die holder and a second lowered position out of contact with the lower die holder,
• providing changing rails continuing from the split rails, extending horizontally outside the reduction press machine, the changing rails having support surfaces flush with the support surfaces of the changing rails,
• providing a plurality of shift rails with support surfaces flush with the support surfaces of the changing rails,
• providing a sideways shift apparatus that moves in the direction of the transfer line so that one pair of the shift rails is aligned with the changing rails, and
• providing a die clamp moving apparatus that moves the upper and lower die holders with the dies, after being removed from the die clamps, from the raised split rails, to the shift rails through the changing rails, in which the upper and lower clamps comprise a plurality of clamping cylinders (112a) that push against upstream and downstream ends of the die holders (110) in the transfer line and make the die holders come into close contact with the loading surfaces of the upper and lower sliders (108);
• (A) placing a spacer between the upper and lower die holders, releasing the clamping cylinders, separating the die holders from loading surfaces of the sliders and removing the die holders from the die clamps, and, simultaneously, placing the upper die holder with the upper die on the lower die holder via the spacer;
• (B) raising the split rails, and resting the upper and lower die holders on the split rails;
• and
• (C) moving the upper and lower die holders with the dies, after being removed from the die clamps, from the raised split rails to the shift rails via the changing rails, by means of the die clamp moving apparatus.