Scania is to offer the further possibility of emission reduction in its city bus and charter coach range with the
Scania is to offer the further possibility of emission reduction in its city bus and charter coach range with the addition of a new low-emission 9-litre engine.
Operators can now take advantage of the latest low-emission technology with the availability of three new Euro 5 diesel engines and a Euro 5 ethanol engine.
Scania Australia National Manager Bus and Coach Trevor O’Brien says the availability of the new low-emission engine in the Scania K-series meant operators could make the jump to the next level of emission reduction with few operational limitations.
The Scania DC9 30 230, DC9 29 280 and DC9 28 320 diesel engines and the DC9 E02 270 ethanol engine use extremely high-pressure injection (XPI) to reduce emissions of particulates and exhaust gas recirculation to reduce emissions of nitrogen oxides (NOx).
The addition of a particulate filter means three of the four new engines are able to meet the tough ultra-low emission EEV rating.
“EGR is fast becoming the technology of choice for operators who want the simplicity of just adding diesel,” he says.
“Euro 5 offers an opportunity to those operators who want to make their operation more attractive to customers or when tendering for work, or simply because they want to do the right thing by the environment.”
The DC9 30 230 engine develops 230hp (170kW) at 1900rpm and 1050Nm from 1100 to 1350rpm. The DC9 29 280 engine develops 280hp (206kW) at 1900rpm and 1400Nm from 1100 to 1350rpm.
The DC9 28 320 engine develops 320hp (235kW) at 1900rpm and 1180 lb ft (1600 Nm) from 1100 to1350rpm.
The ethanol-fuelled DC9 E02 270 engine develops 270hp (198kW) at 1900rpm and 900 lb ft (1200 Nm) from 1100 to 1400rpm.
In addition to XPI, the new engines also feature Scania variable geometry turbocharging (VGT) for cleaner combustion.
The traditional role of the turbocharger is to boost output. Scania has used the potential of variable geometry turbocharging in a way that controls emissions as well as delivering more torque.
Scania XPI is a unique, patented common rail injection system that operates at a maximum pressure of 2400 bar, significantly higher than other systems. XPI affords a greater measure of control over timing and volume of fuel injection to optimise performance and economy.
XPI allows an average pressure of 1800 bar, permitting three precisely timed and measured injections of fuel. A pilot injection reduces combustion noise as well as helping to reduce emissions.
The main injection gives efficient combustion at precisely the right instant, while post-combustion injection stimulates the burning of carbon particulates and can control exhaust gas temperature.
The volume, timing and pressure for each of the three injections are recalculated for each cylinder, for every cycle. The entire process is constantly monitored and adjusted, ensuring each cycle is fully optimised for performance and economy.
Depending on operating conditions, not all three injections are required for each combustion cycle, further minimising fuel consumption.
As the world’s first engines that use exhaust gas recirculation to meet Euro 5, the new Scania 9-litre engines are reliant on the use of ultra-low sulphur fuel.
The current legislated sulphur content of diesel is 50 parts per million. That is set to change from January 1, 2009 to 10ppm, however supplies of ultra-low sulphur fuel are already being rolled out across the country.