A new, hanging-spindle, vertical turning lathe (VTL) has been introduced by Index on which the spindle head is able to move freely in three dimensional space. Utilising technology similar to that of hexapod machining centres, the revolutionary design means that the rotating workpiece is presented to tooling which is fixed in position by a spindle which moves in three axes instead of two as on all other VTLs. Sole UK agent for the German machine tool builder is Geo Kingsbury, Gosport.
Called VerticalLine V100, the machine is capable of chucking components up to 130 mm diameter in small or large batches very productively indeed.
The six-rod, kinematic construction accelerates at 1g to reach 60 m/min rapid traverse in all three orthogonal directions simultaneously.
One needs only to browse a few web sites to see that this rapid feed rate is rarely equalled on other machines in X and Y and it is very unusual to achieve more than 30 m/min in Z (vertical spindle travel).
Rigid, thermosymmetric construction and linear glass scales ensure high turning accuracy, which is promoted further by cooling of the motor spindle unit.
During machining the Siemens Sinumeric 840D control handles all interpolation tasks, so the programmer needs only to work with the familiar X,Y,Z axes.
As with all VTLs, the machine is highly flexible owing to the spindle's ability to perform component load / unload in combination with a conveyor or other workpiece storage device.
This eliminates the need for robotic or gantry-type component handling.
Furthermore, to complement the 8 to 12 stationary or live tools, an extensive variety of additional attachments may be fitted such as laser welding and hardening equipment, a grinding spindle, multiheads, gauges for in-process measurement and assembly jigs.
Thus the very fast chip-to-chip times afforded by the hexapod-driven spindle, with its fast rapids for machining as well as for load / unload (plus elimination of normally slow turret indexing) are combined with the traditional benefits of the hanging-spindle design, namely one-hit completion of complex machining sequences.
Consistent with the relatively small diameter of parts being machined, spindle speed is somewhat higher than usual at 7,000 rev/min, or optionally 10,000 rev/min.
Power output at 100 per cent duty cycle is 24 kW and 10 kW respectively.
The 3.5 tonne machine has a compact footprint of 2.1 m by 2.1 m by 1.5 m and several may conveniently be set up as an automated production line.
The V100 is the smallest capacity machine in an established range of conventional hanging-spindle VTL's from Index comprising the VerticalLine V200, V200 Twin, V250 and V300, the latter having sufficient capacity to turn 315 mm diameter components.