TechArchive

Original article date: February 2000

Gravatom Engineering Systems Ltd established their strong reputation in nuclear engineering, and have since expanded into other areas including industrial automation, original equipment manufacture and pharmaceutical. They recently received a SMART award from the Department of Trade and Industry for an engineering project of outstanding technical merit.

Festo are the world leaders in pneumatic control. In the last five years they have invested over (UK pounds)330 million to stay at the forefront of pneumatics, fieldbus control systems and positioning technology. They have a policy of sharing this knowledge ihrough their training division, Festo Didactic, believing that better trained engineers benefit industry as a whole.

The perfect contacts

The end customer, AEA Technology Battery Systems Ltd, a division of AEA Technology, approached Gravatom to design and manufacture an advanced battery cell welding machine. Gravatom were looking for the partner with the most up to date technology and the engineering expertise to optimise the solution.

Gravatom had worked successfully with Festo on other projects so Festo Automation Consultant, Ian Gemson, was contacted. Together with Festo’s positioning specialist, Product Manager Jim Bannister, Ian liased closely with the Gravatom project team. They developed a solution that delivered the system flexibility required at the right price using the unique Festo servo pneumatic positioning system and fieldbus technology.

An electrifying solution

AEA Technology Battery Systems Ltd. needed a production machine to cost-effectively collate and weld together contact strips on batteries. The jointly developed solution has three main elements:

1. Automatic battery in-feed system
2. Contact strip – feed, crop and weld
3. Weld-to-stack station

Mirror imaged storage racks take 15 trays of battery cells on each side. They are loaded through an alignment mechanism, nicknamed the ‘BBQ Griddle’, to a feed line. This gives the system its ability to run unattended for at least 11/2hours, a considerable advantage.

For maximum efficiency the machine uses a ‘pull through’ approach reducing control complexity and at the same time optimising work flow and machine performance. There is no buffering of stock as the production rate is adjusted to the throughput at the final assembly station. The machine takes just ten minutes to be reconfigured for alternative stack lengths or battery sizes from AA to D. To do this the incremental Servo Pneumatic cylinder movements are adjusted between 10 and 35mm with a positioning tolerance of +/-0.2mm.What is truly electrifying about this system is its adaptive control, this monitors each movement and optimises it for speed, precision and smoothness.

As Barry Elsey, Gravatom’s Project Manager, Industrial Automation, says, ‘This project has proved conclusively how a partnership with the people at Festo can provide the right solution. Working with Ian and Jim has convinced me of the benefits of Festo’s hands-on experience combined with their first class products and advanced technologies – we welded a perfect solution’.

For more information on the broadest range of pneumatic products and world beating solutions in the areas of Fieldbus control and Handling & Positioning call Festo.

• Festo
  Tel: 01252 775057
• Gravatom
  Tel: 01489 896010

February 2000