Drum mowers rotation movement is harmful for the root of the crops. Disc mowers do not harm the crops as drum mowers. In the disc mowers there are oval discs located on the cutter-bar and these discs rotate with 3000 rpm. This rotation creates an air turbulence which uprights the leaned grass. Disc mowers have a safety mechanism against hitting a hard object. In case of a hit, disc mowers make a move backwards to decrease damage to minimum.
