Boring Tool Vibration Minimization by Using VE and Composite Materials

The boring operation is commonly used in the manufacturing process for enlarging the hole size. The boring tool which is used to perform this operation is always exposed thigh level of vibration due to cutting forces. This excessive vibration affects the efficiency and productivity of the boring operation. There are mainly two techniques of vibration minimizations, Active and Passive. From literature reviewed it is found that the active vibration reduction technique is complicated and expensive. Further it is also seen that the scope of passive vibration technique is not fully explored. Previously the impact mass, impact particles etc. are used as passive dampers for boring tool, but its use does not give significant reduction in vibration level. In this paper a passive damper is fitted over the boring tool and vibration level is measured using FFT analyzer under different machining conditions. The experiments were carried out by varying the machining parameters such as spindle speed, feed rate and depth of cut. The passive damper characteristics taken are: materials (i) visco-elastic and (ii) composite (visco-elastic and Aluminium) and damper length (i) 0.3× boring tool overhang and (ii) 0.6× boring tool overhang. The experiments are conducted as per the Taguchi method using L16 Orthogonal array with two repetitions. The effects of boring tool vibration are also checked by measuring surface finish of the work-pieces. The overall level of vibration is significantly reduced with use of passive damper and subsequently enhances the surface finish.