Cutting device

The invention provides a cutting device. A pressing member side inclined surface 65 of a pressing member 6 is pressed down by a clamping block side inclined surface 542 of a clamping block 54, and a bar material is pressed and clamped by a pressing part 621 of a pressing bush 62. An inclination angle [theta] between the clamping block side inclined surface 542 and the pressing member side inclined surface 65 is formed to be 6 degrees. The inclination angle [theta] is formed such that a component force of the pressing is smaller than the maximum friction force between the pressing member side inclined surface 65 and the clamping block side inclined surface 542. Therefore, even if a large reaction force is applied on the pressing member 6 when the bar material 13 is cut, the clamping block 54 and a piston rod 551 do not return to the left direction (unclamping direction). Bouncing of the bar material 13 is prevented during cutting, and a billet can be produced stably with improved cutting accuracy.