New process allows for quick composite repair

A UK partnership has developed a way to repair composite tools needed to make aircraft parts which, the companies say, can save time and money.

The partnership between JR Technology Ltd, Composite Tooling & Engineering Solutions Ltd (CTES) and Retrac Composites Ltd devised the new process to repair composite tools used on the Airbus A350XWB-1000 rear wing spar sections, manufactured by GKN Aerospace.

The partners could carry out repairs for the aerospace industry on-site in the future, wherever the client is based.

Instead of using a large autoclave or oven to accommodate a large composite tool which required repair, CTES and Retrac turned to JRTL to supply eight infra-red lamps and a hot bonding controller with multiple heater mats.  

These allowed engineers to control accurately the cure of the additional prepreg laminate in multiple areas at the same time and cut the curing time of the surface sealer from 18 hours to one and a half.    

Portable repair

The tool in question measures almost 14m in length and weighs 2.75 tonnes.  The geometry of the tool didn’t allow for the sole use of the controller, so infra-red lamps were brought into service to apply heat locally in complex areas of the tool. Local vacuum bags were used to apply pressure in all repair areas.

‘The combination of the lamps and the hot bonding controller gave [CTES and Retrac] the control they required for the cure cycle they needed to do a repair.’ said Paul Rogger, technology director of JR Technologies Limited. ‘It was also portable, so if there’s a requirement for this sort of thing in the future, clients purchasing these items from us will be able to carry out repairs on site.’

‘The solution worked extremely well, saving time on an already tight tool manufacturing programme, allowing the carrying out of repairs, without having to result to the use of ovens or autoclaves,’ said John Jacobs, tooling engineer at GKN Aerospace. ‘The accuracy of the control system coupled with the flexibility of the system will make for very useful tool for the repair and maintenance of composite tools.’

This story is reprinted from material from JR Technologies Limited, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.