The object of this project was to update the concept of aero-engine dressing to the most advanced concepts already used in commercial aircrafts. The existing design concepts and components utilised within the engine dressings have remained largely static for a long period of time; there is little difference in the components and materials used in the engine dressings on the latest Trent engines to the early RB211’s.
In today’s competitive aero-engine market, the primary product discriminators are cost-driven. Typical cost savings of 20-30% delivered by PMCs in replacing incumbent metal parts; therefore, provide added incentive for wider application of these materials. With these impressive advantages on offer, it may seem difficult to understand why composite materials do not dominate the latest civil and military engines.
COMPipe allowed the design and manufacture of an agreed set of non-metallic pipes and support systems to replace traditional metallic variants in engine dressings. It also identified the manufacturing processes that could be used to scale up the production requirements to meet future delivery needs.
The scientific and technical objectives to reach along the project were:
- To design and develop a new concept of non-metallic pipes and fittings suited for aero-engines, specifically drains, scavenge, sensor and vent lines
- To select materials meeting the required environmental constrains, both in the range of temperatures and in the chemical resistance to different products present in the aero-engine, such as Skydrol hydraulic fluid, oil and aviation fuel.
- To develop one or more manufacturing practices and to improve existing methodologies driving to:
- To a product standard with a near to zero wall's porosity,
- To produce 3D geometries of according to the already existing metallic technology,
- To assess the future full automation of the process,
- To ensure that Nadcap qualification will be reached in a short time.
The scientific and technical achievements reached from the project were:
- Design and development of a new concept of non-metallic pipes and fittings suited for aero-engines, specifically those for drains, scavenge, sensor, vent lines and oil.
- Selected materials meeting the required environmental constrains, both in the range of temperatures and in the chemical resistance to different products present in the aero-engine, such as Skydrol hydraulic fluid, oil and aviation fuel.
- Developed manufacturing practices to improve existing methodologies driving to lower cost production. Notably these have been development of a thermoplastic and thermoset matrix composite pipe.
- Additionally, the project has managed to develop a solution which incorporates the technology required to meet the requirements of fuel carrying systems.
- The project has produced a thermoplastic composite product standard that has been shown capable to reach zero wall porosity and high pressure retaining capability.
- The project has proven the ability to replicate the 3D geometries compatible with existing metallic technology.
- In the case of thermoplastic pipes, the present manufacturing capability and future full automation of the process has been assessed and future developments identified.
- To meet the requirements of fire performance, the project has developed new standards from the existing standards of Rolls-Royce in order to achieve measurable performance in the composite product.
- The project has provided technical results that can be used to upgrade existing elements of metallic pipe systems.
- The project has demonstrated the applicability of existing technologies for fire resistant composite materials.
- Through a series of rig tests, the project demonstrated that composite pipe assemblies are capable of meeting, or even exceeding the performance and environmental requirements for an aero engine.