This is a typical in-feed line for a flatbad die cutter equipped with pre-feeder. The stacks are discharged in the center of the line by the shuttle car, and later on the piles are separated on the conveyor just upstream the pre-feeder. The in-feed line include centering device and rotating device. The rotating device is operating just to rotate 180° the piles warped on a side, in order to increase the runnability of the machine, further on the centering device aligns the pile in the center of the line. The in-feed line operates in full automatic way, in order to accumulate as much as board as possible.