Donaldson Co. Inc.’s LNFmuffler system is designed for model year1993 to 2006 high nitrogen oxide engines.It can reduce particulatematter emissions by more than 90 percent.
Donaldson Co. Inc.
Sales Manager Todd Lewis says Donaldson’s newest products for school buses are the LNF and LXF mufflers as well as the SEF Muffler System.
The LNF and LXF products reduce particulate matter emissions by more than 90 percent. The LNF muffler is designed for model year 1993 to 2006 high nitrogen oxide engines, while the LXF muffler is designed for model year 2002 to 2006 low nitrogen oxide engines. Both muffler kits are equipped with an Emissions Device Monitor that indicates when DPF cleaning is required. The monitor also sends alerts to the vehicle operator through an in-cab display when abnormal or undesirable operating conditions are detected.
Finally, the LNF and LXF mufflers are passive systems. The exhaust gas temperature profile for the LNF is: greater than 235 degrees Celsius for at least 40 percent of the time or greater than 300 degrees Celsius for at least 10 percent of the time. The temperature profile for the LXF muffler is: greater than 245 degrees Celsius for at least 40 percent of the time or greater than 310 degrees Celsius for at least 10 percent of the time.
Donaldson’s SEF Muffler System uses semi-active DPF technology and is designed for on-road, non-EGR model year 1991 to 2006 engines.
“The SEF requires a regeneration station. Depending on the duty cycle, they usually go two to three weeks before you have to plug them in,” Lewis says, adding that the SEF system is easy to install.
In addition to reducing diesel particulate matter by more than 90 percent, the SEF muffler is effective at reducing hydrocarbon and carbon monoxide emissions.
The junction box that comes with the SEF system houses the connections for the DPF regeneration station. The station can control up to two DPF regeneration cycles consecutively.
“One of the other new products we have is a closed crankcase filter system. It improves in-cab air quality by reducing the interior particulate concentration by about 20 percent,” Lewis says.
Donaldson’s Plastic Spiracle Crankcase Filtration Systems are CARB- and EPA-verified when combined with the company’s diesel oxidation catalysts.
Engine Control Systems’ Purifilter Plus dieselparticulate filter is a hybrid — it’s not a completely active system. It works in a passive manner when the temperature of the exhaust is sufficient, meaning that it requires less plug-in intervals for regeneration.
Engine Control Systems
Engine Control Systems offers the Purifilter Plus and Purifilter DPFs for school buses, which are verified by CARB and the EPA. Sonya Clark, regional sales manager for Southern California, says they reduce particulate matter emissions by 85 percent.
She adds that the Purifiliter Plus, which can be used on school buses outfitted with 1994 to 2006 model year HD engines, including those with EGR technology, is the most commonly used between the two DPFs.
“The Purifilter Plus is a hybrid, so it’s not a completely active system. It works in a passive manner when the temperature [of the exhaust] is sufficient, requiring less plug-in intervals for regeneration — it’s not a daily plug-in interval,” Clark explains.
The Purifilter is a passively regenerating DPF that requires no operator interaction. Clark says this filter would benefit pupil transporters whose buses travel on a lot of rural routes.