Avilion has drastically reduced mill-turning cycle times with a new type of lathe from Index that supports and moves the turrets using kinematically-actuated plates sliding over the bed.
Luxury tap and shower system manufacturer, Avilion, has drastically reduced mill-turning cycle times with a new type of lathe from Index that supports and moves the turrets using kinematically-actuated plates sliding over the bed, instead of conventional compound slides. It is the first of the German manufacturer's C-Series machines to be installed in the UK and was supplied through sole agent, Geo Kingsbury Machine Tools. Said Steve Pope, Manufacturing Development Engineer at Avilion's Rainham factory, 'The twin-spindle, triple-turret, fixed-head lathe produces parts in a single set-up in half, and sometimes one third, of the time taken on our single-spindle, single-turret machines.

Even comparing like with like, surprisingly it is around 30 per cent quicker than our conventional twin-spindle lathes.' Such fast cutting cycles result in part from the opposed spindle having 150 mm of X-axis movement in addition to 600 mm of longitudinal travel - a configuration normally found only on a sliding-head lathe, according to Mr Pope.

The second spindle's movements can be coupled electronically with the two-axis motion of the lower, double-sided, 24-tool turret, which can simultaneously be working with the upper turret at the main spindle, allowing three tools to be in cut simultaneously.

Each turret has a 70 mm Y-axis for extra versatility when mill-turning highly complex components, easily achieving tolerances down to +/- 0.02 mm on seals, +/- 0.05 mm for other features.

Rapid traverse rates of 25 m/min in X and 50 m/min in Z, and acceleration of 1g, are achieved by not having to move a bulky compound turret slide using conventional ballscrews, leading to short idle times.

The distance between the turret centreline and the point at which it is driven is shorter than for a compound slide, making it several times stiffer and more accurate.

Glass linear scales provide positional feedback.

Continued Mr Pope, 'We will produce 30 to 40 of our most complex brass components on our Index C-Series lathe from 13 mm to 65 mm bar, and billets up to 80 mm in diameter, as we prefer to machine our components from solid rather than rely on castings.

Every part will be machined on the reverse and a cycle will often include 50 per cent milling, drilling and tapping; sometimes a lot more.

'Such is the capability of the machine to slash cycle times, 24 hours a day, and reduce unit manufacturing cost that we have been redesigning our components, where necessary, to maximise the capabilities of the C65 lathe.' Again with high productivity in mind, Avilion has invested in one of the very few Kurt Breuning Profimat bar magazines in the UK to feed the Index lathe.

Changeover to a different bar diameter can be carried out in seconds, or a maximum of 10 minutes if the liner needs to be exchanged.