Victrex Peek polymer used in Boeing TBMS

Edited by the Engineeringtalk editorial team Jul 14, 2009

Messier Bugatti has selected Victrex Peek polymer and ATM Plasturgie to produce key plastic parts for its new tire and brake monitoring system (TBMS).

The new system measures tire pressure and the temperature of the brakes in the landing gear of the Boeing 747-8.

Nine plastic parts, including the main hubcap, have been designed using Victrex Peek, with the primary objective of reducing weight compared with a conventional material such as aluminium, while maintaining the mechanical strength and chemical resistance of the parts in the system.

The implementation of Victrex Peek in the system has resulted in a 40 per cent weight reduction, a saving of almost 10kg for each set of landing gears.

The specifications for this new system are extremely stringent.

All landing TBMSs must be able to withstand repeated hard landings as well as impacts from debris on the ground and must survive being exposed to ozone and the chemicals contained in jet fuel, hydraulic fluid and de-icing solutions.

Samuel Ratgras, leader of the mechanical project, and Bertrand Maes, responsible for the project at Messier Bugatti, explained that the design of the unit allows instantaneous contact-free measurement of air pressure in the tires and the temperature of the brakes during take-off and landing.

The hubcaps include a conduit that allows a rim-mounted sensor to communicate with onboard systems, providing real-time data to the cockpit.

Maes said: 'The parts used in the landing gear are subject to extreme stresses, ranging from -55C at maximum altitude to +177C on the tarmac and the specification requires peaks of 204C for one hour.

'Further, the components must be able to handle accelerations of 100G.

'That meant we needed a material that would maintain its strength throughout the entire temperature range, particularly given the frequency of impacts resulting from debris on runways.

'Using Victrex Peek polymer allows the hubcap to withstand extreme conditions.' According to Didier Padey, market development manager at Victrex: 'Victrex Peek polymer maintains its mechanical properties even in hot/wet environments.

'With a continuous-use temperature of 260C, this polymer has proven to be very stable when compared with other thermoplastics.' In addition to outstanding thermal performance, Victrex Peek polymer provides excellent fatigue performance, wear and chemical resistance.

Padey added: 'This unique combination of properties has allowed Victrex Peek polymer to successfully displace conventional materials in a growing number of aerospace applications and also to be referenced by and receive type approval from many OEMs and manufacturers, including Boeing.' After a thorough review of potential suppliers of plastic parts for aerospace applications, Messier Bugatti chose ATM Plasturgie, a company that specialises in high-precision plastics.

The company is certified according to the EN9100 and ISO 9001 standards.

It offers a full range of services related to plastics, from the design of parts and the manufacture of tools to injection and delivery of series-produced parts.

The level of expertise ensured that the entire project was controlled and carried out in-house, optimising prices and scheduling.

The company's machinery, which comprises electric presses that are extremely compatible with the use of Victrex Peek, and the expertise associated with processing, were other factors in favour of selecting ATM Plasturgie.

According to Olivier Tonin, the managing director of ATM Plasturgie: 'The project is a success because Messier Bugatti integrated us upstream of the phase of designing the parts.

'We were able to help our client to develop 'intelligent' parts, thanks to the injection simulation.

'We also contributed our expertise as a mould manufacturer and processor to making parts that can be produced industrially, thereby reducing the fine-tuning phases.

'The close co-operation between Victrex, Messier-Bugatti and ATM Plasturgie allowed development time to be reduced by 30 per cent.'.