Control of chatter vibration in double inserts turning with phase difference of modulations.

A double inserts turning with two inserts mounted on a tool shank is proposed to control regenerative chatter vibration in turning of workpieces with low rigidity. In the presenting turning, the forward and the backward inserts are placed with a position offset in the feed direction; and those inserts are also clamped with a height offset each other in the cutter height direction. A part of the waved surface formed in the preceding cut by the forward insert is concurrently removed by the backward insert placed at a higher position than the rotation center of the workpiece. The regenerative effect, then, is controlled to suppress the chatter vibration by cutting the outer modulation with a time delay. This paper describes the principle of the double inserts turning for control of chatter vibration based on phase difference of the outer and the inner modulations. An analytical model, then, is presented to associate the regenerative effect with the offset parameters of the inserts. The cutting tests were conducted to verify the double inserts turning of a slender workpiece with the offset parameters of the inserts obtained by the analytical simulation. The chatter vibration is controlled effectively by adjusting the offset parameters of the inserts corresponding to the turning parameters. • A novel turning operation is proposed to control regenerative chatter vibration in double inserts cutting by two inserts. • Regenerative effect can be controlled by cutting a part of the outer modulation with phase difference by using two inserts. • An analytical model is presented to determine the offset parameters of the inserts for control of the chatter vibration. • The double inserts cutting may be simply applied to normal turning operations without any additional equipment. [ABSTRACT FROM AUTHOR]