Thursday, December 21, 2006

Turning centre deploys 80 tools without a magazine

A 15-axis mill-turn centre of twin-opposed-spindle configuration and may be equipped with two, three or four disc turrets - deploying up to 80 tools without a tool magazine.

The new, German-built Traub TNX65/42 mill-turning centres from UK agent, Geo Kingsbury Machine Tools, are of twin-opposed-spindle configuration and may be equipped with two, three or four disc turrets, each capable of holding 10 driven or static tools on both faces using double toolholders. So up to 80 tools can be accommodated in this conventional design of lathe. Normally for a CNC lathe to deploy such a large number of tools, its design is based on a single-station turret head with automatic tool change (ATC) from a magazine outside the working area.

As a conventional turret tends to be more robust than its ATC counterpart, higher accuracy machining may be achieved, added to which the 10-tonne TNX65/42 is constructed on a heavily ribbed, cast iron slant bed that dampens vibrations and promotes close tolerance machining.

Tool change is faster with a disc turret than when cutters are exchanged from a magazine, leading to higher productivity as well.

Balanced turning of slender workpieces or two dis-similar machining operations performed at the same time are established advantages of twin-turret turning, which is achievable at both spindles simultaneously.

The TNX65/42 takes the technology a stage further, however, with the possibility of tools in three turrets cutting simultaneously at either spindle.

In addition to travels in X and Z of 650mm and 175mm respectively, there is +/-40mm of Y-axis movement on each turret, enabling keyway milling, off-centre drilling, side face milling and similar operations to be carried out.

Even more complex components may therefore be completed in one hit, with all attendant benefits including less work-in-progress, shorter lead times, zero fixture costs and reduced manning overheads.

The result can be cycle times so quick that they would normally be associated with a multi-spindle auto.

Of symmetrical design, the machine has its turrets arranged on independent slides above and below the spindle centreline, giving maximum versatility for optimising cycle times.

Furthermore, the headstock is thermo-symmetrical and the synchronous, C-axis motor-spindles are of identical rating at 24kW / 5,000 rev/min for the 65mm bar capacity machine and 28kW / 7,000 rev/min for the 42mm bar model.

Hybrid bearings are fitted as standard for increased service life.

Control is provided by the TX8i-s running, as usual, Traub's in-house developed software.

It is optimised to the manufacturer's lathes and is backwardly compatible, allowing programs to be run that were created on earlier controls.

Realistic 3D simulation shortens set-up time and avoids collisions when producing first-off components.

On-line and off-line programming with powerful synchronisation and optimisation of up to four machining sequences can be provided by Traub's optional WIN FLEX IPS graphical object-orientated software.