The Topic Manager for this work, Saab Aerostructures, are looking to use RTM technology to increase the production rate of their Flaperon parts to meet a rising customer demand. The flaperon geometry includes specific challenges that require careful tool design and control over the part shape to ensure that the 3 metre-long final component can be fitted directly to the aircraft without costly rework to the part, or even the tooling, during production.
The FLEX project will develop a tool with in-situ, automated correction of distortion caused by the internal stresses build-up during composites processing. The tooling concept will include process automation and optimisation elements in order to offer an RTM manufacturing solution that can meet the present-day production outputs required by the aerospace industry. The project main goal is to offer a tooling solution that automatically corrects part distortion and incorporates enabling technologies for increased productivity (almost double of the SoA) with traceable aerospace quality of the produced parts.
The FLEX project has the following objectives:
1. To design an RTM tooling system that will feature decreased lead times and increased productivity. The tooling will have the following features:
a. Novel distortion compensation capability in order to reach the final mould lines (final shapes) fast with minimum design / rework iterations.
b. Capability to handle increased productivity of up to 200 parts per month thanks to careful curing process optimisation and introduction of automation in every stage of the manufacturing process.
2. To demonstrate the capabilities of the developed technologies in a small-scale mould that will be representative of the real scale tool. The small-scale mould will be used to conduct trade-off and validation studies. The final design of the real scale mould will be ready on M16 after a Critical Design Review.
3. To study and realise process automation concepts for the manufacturing of the demonstrator (flaperon). Areas of investigation will be the preform/fibre placement, the resin injection process and mould cleaning. These automation steps will be included in the initial tool concept but will be finalised on M12. They will be included in the final mould design but will be validated on the small-scale tool in M24.
4. To fabricate a real scale functional tool that will incorporate the developed technologies and will be eventually used for the fabrication of a relevant demonstrator (flaperon) under the responsibility of the Topic Manager. The final tool will be ready in M20.
The FLEX tooling concept will bring a number of benefits to the production of composite flaperon or similar aerospace components. The primary benefit is to reduce the development costs and lead time for RTM tooling of composite components through removal of the trial-and-error aspects of initial part manufacturing trials. The automatic compensation system will remove the need to rework the tooling to compensate for the part distortion, a significant time and material cost. This compensation system will also allow the tooling to compensate for ply misalignment during manufacture to ensure that the yield of the manufacturing process can be increased through a reduction in scrap and rework costs on components.
In addition, the integral heating within the tool reduces the infrastructure needed to support high production rates (no ovens required) and the lower thermal mass of the tooling will serve to reduce the cycle times. Further reductions, through cure optimisation, will ensure that the part receives the correct heat profile to ensure a full cure without the hugely conservative safety factors and with documentary evidence to support the cure cycle received to meet aerospace production requirements.