The main principle behind the VDI system is a quick-change, cam-operated clamping system for each tool holder within the tool disc or turret. Tool changes can therefore be performed within seconds, rather than within minutes as with the traditional block system. The tool holders can also be preset away from the lathe on a pre-setter since VDI capable turret ensures accurate and rigid positioning of the VDI tool holder.
Fig.1. VDI tool holder retention system
The VDI tool holder retention system provides an accurate and rapid method of affixing tools to the turret plates. The round serrated tool holder shank fit into tool pockets which are located on the face or edge of the tool plate clamping mechanism using a single Allen wrench to achieve precise, rigid and secure locking of the VDI tool holder.
The hardened and ground serrated wedge, see the sample picture, accurately locks the tool holder into position and securely pulls it back to the surface of the turret. Typical changeover time for a pre-set VDI tool holder is less than fifteen seconds!
In today's demanding and flexible manufacturing environments, fast changeover and set-up times are essential in order to stay profitable. Quick-change tooling contributes to this necessity and adds many hours of productive turning capacity to a CNC lathe.
Just to add that the VDI tool holders are available in static and live (motorized) versions which allow a CNC lathe to perform milling and radial drilling operations in one cutting cycle!