Winton: go vane for efficiency gains
Andy Gear, general manager at Winton Engineering, makes the case for the use of vane compressor technology in on-board power solutions for commercial vehicles
When a fleet operator requires flexible mobile power solutions, including compressed air, electric, hydraulic or even high-pressure water jetting, on-vehicle power can be the ideal solution. It can be used for a multitude of tasks, including the operation of road drills, breakers, hand tools, site lighting and electrofusion equipment.
Compared to the traditional approach of using separate pieces of plant, on-vehicle power solutions deliver many benefits. These include a cleaner, safer working environment for employees, reduced operational noise levels, lower exhaust emissions and improved vehicle utilisation.
Manufacturers of on-vehicle power solutions will either use vane, screw or piston-driven compressor technology within their products – and while this might not seem overly significant, it can actually make a big difference to the bottom line. Not everyone realises that different types of compressors can vary significantly in their performance – and therefore their efficiency – and so it’s worth fleet managers taking a closer look at the solutions on offer.
For a compressor to operate efficiently, the internal air leakage paths must be kept to an absolute minimum – because air lost during compression equals lost energy. If internal leakages are low, the volumetric efficiency is increased, and the power required for a measured unit of delivered air is reduced.
A rotary vane compressor is made up of a rotor with longitudinal slots, which house individual sliding vanes. The rotor is offset within a stator (a cylinder), in which it rotates on maintenance-free white metal bushes. While the rotor turns on its axis, the vanes are pushed against the stator wall by centrifugal force, and the air is compressed.
Because their design results in minimal internal air leakage, vane compressors are volumetrically more efficient than screw compressors. The vanes move freely in their slots, but are always in contact with the internal surface of the stator (albeit not directly, due to lubrication), so the air seal is near-perfect.
The clearances between the rotor, stator and end covers are also efficiently sealed by oil that is injected into the stator to lubricate the moving parts and to cool the air during compression. This means that a vane compressor typically produces more air per kilowatt than a screw compressor and therefore consumes less power.
The Mattei rotary vane compressors used in our on-vehicle power solutions generate up to 20 per cent less load than other compressor types, which delivers a fuel saving of up to 10 per cent.
Vane compressors also operate at lower speeds than screw compressors, from a direct drive coupling, which in turn leads to lower power consumption. We have developed systems to reduce the upper engine running speed from 1,900 to 1,580rpm, and tests indicate a significant additional saving of up to one litre of fuel per hour.
Based on a fuel price of £1.00 per litre at 400 hours per year, this can deliver a potential combined fuel saving of up to £400 per annum, per vehicle. The savings for customers operating a whole fleet of vehicles can therefore be substantial.
In addition, the use of synthetic oil in the compressors delivers extended service life and reduces whole life operational costs, and oil change intervals are extended to 36 months or 1,200 hours.
As well as reducing fuel consumption and whole life operational costs, the use of vane technology also significantly reduces operator exposure as well as general noise pollution.
Winton designs, manufactures, installs and maintains on-vehicle power systems suitable for fitment to most commercial vehicles from 3 to 26 tonnes. They deliver compressed air from 35-120cfm at pressures of 100 to 180 psi, and can be used in conjunction with hydraulic or mobile electric power delivering up to 106Kva at 400v.
Winton will be promoting its on-board power offering at this year’s Commercial Vehicle Show, which takes place between 26-28 April at the NEC Birmingham. The team can be found on stand 5H110.
