To remove chips in deep drilling, it is essential to use retreat cycles and to use efficient lubrication.
The principle of vibratory drilling is to create an axial oscillation to split the chip
in small pieces, which are naturaly evacuated..
Two principles have been developped :
• Axial spring : self excited vibrations.(Limitation : it is necessary to control all cutting parameters to avoid vibration stopping, which would bring a disaster, and also to avoid strong vibrations)
• Axial cam : drill's position is controled.
(Limitation : the cam must not be rotating with the drill.)
Vibration drilling is already widely applied in aerospace and in a variety of processes and materials.