Composite aero-engine pipes could offer 50% weight savings

8 May 2013 Published by

An R&D programme to develop non-metallic pipes for aero-engine applications could deliver weight savings of up to 50%, according to current estimates from engineers at Sigma Components.

The predicted weight savings were announced as Sigma Composites provided a mid-point update on its €1.8m Clean Sky funded COMPipe project at the Composites Engineering show at the NEC, Birmingham.

The team is currently working on a two-year project in conjunction with TWI Ltd. to develop and test non-metallic pipes for aero-engine applications.

Mike Andreae, Head of Business Development at Sigma Composites, said: “Although polymeric pipes are already used in some aerospace applications, the COMPipe project addresses the use of composite pipes in more technically-challenging engine environments.

“Engine components need to operate at elevated temperatures and pressures compared to other aircraft components. They also have to be non-porous, fluid tight and meet stringent fire resistance requirements.

“Developing lightweight, composite materials that meet these requirements and can also be formed to replicate existing 3D pipe geometry is a real challenge. Then, of course, you also need to develop new end fittings to connect the pipes with other engine components, all while ensuring that weight reduction gains are balanced by maintaining affordability.”

Sigma’s team of design and project management engineers has been working closely with a number of subcontractors, research organisations and universities to develop solutions to these challenges over the last 12 months, with promising initial results.

Mike continued: “A key part of the programme has been to develop and optimize new braiding technologies and we’re grateful for the support of Manchester University in this regard. We’ve already manufactured straight, thin-walled, non-porous carbon-fibre reinforced PEEK pipes and are now developing a number of techniques to reform these into the 3D shapes required by engine designs.

“We’re also exploring a range of fire protection options – such as thermal protection liners and coatings and advanced metal plating systems – and developing new fittings that significantly reduce both weight and space in the engine.

“Based on current results, we estimate that weight savings of up to 50% per complete pipe assembly could be achieved using these new techniques. It’s exciting news for the industry as, even if composite pipes prove suitable only for limited engine applications, the total weight saving per engine could be very significant.”

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