TPi October 2012

products & developments

High precision tubes in space plane pre-cooler tests

above and beyond the flight envelope as well as preliminary cryogenic cooling.

At the Farnborough Airshow earlier this year, Reaction Engines announced that its revolutionary Skylon space plane has passed another significant milestone following the second phase of successful tests on the Sabre engine pre-cooler. The high precision heat exchanger tubes manufactured by Fine Tubes are a key component to the cooling system of this hybrid engine, which is on course to transform not only space travel but also air transport around the world. The Sabre engine, developed by Reaction Engines and a team of over 30 British engineers, has the ability to operate as a jet and rocket engine. This hybrid function will be capable of propelling the Skylon space plane at up to five times the speed of sound, allowing a new generation of aircraft to fly to any destination on Earth within four hours or, when in rocket-mode, directly into space at twenty five times the speed of sound. With the second series of testing, Reaction Engines has proven the pre-cooler’s aerodynamic stability and uniformity, its structural integrity, freedom of vibration across a wide range

Critical to the performance of the Sabre engine is a heat exchange system that cools air for the engine intake. This technology will chill incoming hot air from over +1,000°C to -150°C in less than 1/100 th of a second, enabling the space plane to effectively double the current limits of jet engine speeds. Fine Tubes’ team of engineers and metallurgy experts in Plymouth, UK, has been instrumental in developing crucial tubes for the pre-cooler system and has worked in partnership with Reaction Engines to come up with a breakthrough in aerospace heat exchanger design. “Like the Sabre engine itself, the tubing in its heat exchanger is an engineering marvel,” explained Alan Bond, corporate programmes director for Reaction Engines. “There are a few other companies which produce the kind of high technology tube we need but the Fine Tubes product is extremely high quality, meeting all the project specifications. We are very pleased with its performance.”

Heat exchanger tubes with 40-micron wall thickness from Fine Tubes

to minimise weight and to act effectively as a heat exchanger, but also very strong because of the heat, pressure and forces involved. Fine Tubes specially designed a high pressure tube made from Inconel, a nickel alloy that is very resistant to temperature and well suited for use in extreme conditions. The high specification tubes for this pre-cooler system have an outside diameter of less than a millimetre and a wall thickness of just 40 microns, whilst maintaining structural integrity at extreme conditions. UK science minister David Willetts recognised the significance of the Skylon development when he visited the Farnborough International Air show: “The engine being developed by Reaction Engines is a potential game- changer in terms of space technology. This successful testing validates the assessment made of the engine concept by the UK Space Agency back in 2010 and is yet another example of the UK’s world class space industry. It would be a fantastic achievement if we could one day use this home-grown technology for our own commercial space launches.” Fine Tubes has a fully integrated facility for the manufacture and research and development of high quality precision tubes in seamless, welded, and welded and drawn forms. The company is a leading manufacturer of high precision tubes in stainless steel, nickel, titanium and zirconium alloys, and the standards and specifications for these tubes and coils are extremely high, aimed at applications in the most hostile operating environments.

Each engine uses over 2,000km of tubing, which has to be extremely thin

The groundbreaking Skylon space plane

Fine Tubes Ltd – UK sales@fine-tubes.co.uk www.finetubes.com

44

Tube Products International October 2012

www.read-tpi.com