Saturday, June 24, 2006

Destroyed subcontractor wins with turning centres

Subcontractor Colbree Precision was based within two hundred yards of the Buncefield depot and the blast destroyed its factory and most of its equipment.
When the Buncefield petrol storage facility in Hemel Hempstead exploded last December the effect on neighbouring companies was devastating. subcontractor Colbree Precision was based within a two hundred yards of the depot and the blast destroyed its factory and most of its equipment. But what could have been a complete disaster for the company has actually allowed it to develop new ways of working by investing in three new Nakamura-Tome turning centres from UK representative Turning Technologies.

As director Steve Bree explains, Colbree makes most of its smaller turned parts on bar fed sliding head machines, but before the fire it only had single spindle CNC machines for parts bigger than 32mm diameter.

Not only was Steve unhappy with their reliability, but they didn't fit in with his desire to cut out costly and time consuming multiple operations.

When the single spindle machines were destroyed in the fire Steve wasn't sorry to see them go.

'Although we lost that larger CNC capacity, we had already been looking round for alternatives - and in particular we were thinking of investing in Nakamura twin-spindle twin-turret lathes so that we could expand one hit machining,' he says.

'Obviously, in many ways we would have preferred it if the fire hadn't happened, but when it did we tried to make that work to our advantage as an opportunity to change the way we worked.' The Nakamura machines that Colbree invested in - two WT-150 turning centres and one Super NTJ - are all twin-spindle, twin-turret machines that allow complete components to be produced in one set up.

The WT150 machines have 51mm bar capacity, the Super NTJ has 65mm bar capacity.

All three machines are equipped with 24 tool stations per turret, including 12 driven powerful driven tool positions, and are designed to be highly precise, rigid, yet compact production machines.

The Super NTJ also has a +/- 90o B-axis on the upper turret.

This means that the parts can also be machined on multiple angled faces and contour milled in one set up during the turning cycle.

Colbree's major customers in sectors such medical equipment, defence, oil and aerospace often require complex parts with many auxiliary milled and drilled features, which had required further operations on machining centres.

With the new Nakamura machines these can easily be completed in one hit - and the B-axis on the Super NTJ opens up even more possibilities.

'With the B-axis we can actually swivel the turret round and do features such as angled holes.

The only way we could do this before was as another operation on a milling machine.

Doing it on the same machine as the turning obviously reduces the manufacturing time and maintains accuracy.

We used to have three milling machines and now we have cut that down to one - the more work you can do while you are turning the better,' says Steve Bree.

'With these new machines we can do things we couldn't do before and improve cycle times on the work we are already doing.

They have made us more competitive.' The speed with which Colbree has bounced back from what could have been a crippling blow has been impressive.

It was back in full production in new premises within eight weeks of the blast - thanks to good disaster recovery insurance and suppliers who were prepared to make an extra effort.

'Turning Technologies pulled out all the stops to help us back into production as quickly as possible.

They took a chance on our verbal order and were able to rescheduled and reallocate machines.