Hydrovane chosen as sole supplier of 800 compressors with its unique solution for New Bus for London (NBfL)
Wrightbus Limited, manufacturer of the New Bus for London (NBfL) has selected Hydrovane compressors to power the pneumatic systems on-board all 800 of the hybrid-powered vehicles - soon to become a familiar site in the United Kingdom's capital.
Hydrovane has custom-designed the compressor package at its facility in Redditch to provide very lightweight and quiet performance, in a compact unit capable of being integrated easily in to the new bus design.
The NBfL uses the latest, green dieselelectric hybrid technology, with a turbodiesel generator providing power to the bus's batteries, which in turn power the Hydrovane compressor on board.
Each bus has three separate doors alongside all of the other air systems, so air demand is considerable, but the compressor unit easily provides all of the pneumatic power demanded. This includes air for the brakes, door mechanisms and the ability for the bus access-platform to lower to kerb level; a legal requirement to enable easy passenger accessibility.
Excess weight, in particular, is of prime concern as it can adversely affect fuel consumption, so Hydrovane designed the new compressor to be very lightweight, with an integrated dryer and AC electric motor with inverter technology, saving 50% of the weight of a conventional DC unit. Additionally, the AC electric motor requires no maintenance compared to a DC equivalent, and is available at a lower initial capital outlay.
Wrightbus has developed the vehicle to accommodate the maximum number of passengers, using clever space-saving techniques wherever possible. This means that available ancillary equipment room is at a premium and required Hydrovane to design a highly compact solution that could be installed underneath the front stairwell.
An integrated, air on demand twin-tower dryer provides clean, dry air, which, coupled with the compact motor and drive, has provided Wrightbus with an easily integrated, single module.
In addition, the Hydrovane compressor is water-cooled; a further space-saving feature as it requires no ventilation or bulky air/oil heat exchangers making it easy to install in very tight spaces without affecting performance.
Varying air demand
Compressor running is matched to meet the changing demand for air. Inverter drive technology controls the speed of the compressor to provide the amount of air required by the vehicle systems at all times.