The Influence of Tool Holder Technologies on Milling Performance

The quality of machined surfaces is significantly influenced by machine vibrations caused by the cutting process. Whereas most publications ignore the influence of the tool holder, this paper considers the dynamic behaviour of the whole cutting system consisting of spindle, tool holder, tool and workpiece. Therefore modal and operational vibration analyses were performed to describe the damping and operational characteristics of two competing tool holder technologies, namely heatshrink (HS) and hydraulic expansion (HE). It is shown that HE has higher damping rates than HS. Therefore, HE showed mainly better surface qualities, a 10% higher productivity and an up to 300% higher achievable life time of tools.