In these environmentally sensitive times, getting rid of used oil and filters has
become a much more costly enterprise. According to a recent estimate by the Filter Manufacturers Council, approximately 400 million oil filters are used
annually in the U.S. alone. The disposal of these used filters generates approximately 170,000 tons of scrap metal and 90 million gallons of used oil.
Approved disposal of these levels of waste product adds significantly to the cost of operation for engine-powered users.In an effort to alleviate filter disposal problems, Nelson Division of Nelson
Industries, Inc., has developed a full flow filter system designed to dramatically extend filter element life and thereby reduce disposal requirements. The
Eco-Clean system, introduced at the SAE Off-Highway Show in Indianapolis, can be used for engine lube and hydraulic system filtration in on-highway, off-highway, stationary and marine equipment. The
filter element is designed to allow 10 or more oil change cycles before replacement, according to the
company. In addition, because the method of filter cleaning requires no special tools – only access to a
compressed air source – filters can be cleaned in place on the equipment, with no disassembly required.
"There has been an increasing demand for extended drains for engine oils, and operators are also
looking to reduce disposal costs," said Chris Holm, design engineer at the Stoughton, Wis., company. "We've been working on this product for quite some time and we believe it will address those needs,
along with improved filter effectiveness."
The Eco-Clean filters are available in a variety of sizes for heavy-duty truck, bus, agricultural, industrial,
construction and marine equipment applications up to 40 gpm. In engine lube oil and compressor applications, they can accommodate operating pressures to 225 psi, and can operate at up to 1000 psi in
hydraulic applications.
The filters consist of three basic parts, a cast aluminum filter head, the filter element and a single-piece,
extruded aluminum filter housing. The filter element incorporates the proprietary Clean-Pro cleanable
synthetic media that is contained in a one-piece shell open at one end. In retrofit applications, the
element/housing assembly comes with a mounting plate that allows use with most standard filter heads, including spin-on filter mounting heads, the company said. The housing and adapter are intended to
remain in service for the life of the equipment and have been designed to withstand 1 million cycles of pressure fatigue testing.
Radial seals are used between the equipment and adapter and between the adapter and the shell to
ensure leak-free operation. The filter element "floats" inside the sousing on the radial seals at both ends.
This, the company said, eliminates the need for a spring to hold the element in place and facilitates easy assembly and disassembly of the filter when the filter element must be replaced.
At the base of the filter housing are two standard connections. The center connection is an inlet for
admitting the compressed air used to clean the filter. The offset connection is a standard quick connect
coupling used to attach a drain line. The drain line directs oil out of the filter to a waste container when compressed air is applied to the air inlet during cleaning.
In normal operation, oil flows from the outside of the filter elements to the inside like conventional filters.
The filter media holds filtered contaminant particles. Filtered oil flows out of the filter through the center
of the adapter. At the end of an oil drain interval, when a conventional filter would be replaced and disposed of, the Eco-Clean is instead cleaned and reused.
The cleaning operation is designed to be quick and easy. A standard air chuck is used to apply compressed air regulated to 15 to 150 psi to the air inlet fitting.
After oil stops flowing from the drain line, the compressed air and drain lines are removed and the system is topped off with makeup oil to replace the amount removed during the cleaning process.
The cleaning process generally takes under two minutes, the company said. After cleaning, the equipment may be immediately placed back into service. When the filter element reaches the end of its
useful life – typically more than 10 drain cycles, depending on the application – the filter element is
replaced. During replacement of the element, the inside of the filter housing is cleaned to remove remaining oil residue.
The Eco-Clean filter system under went a variety of testing during its development, including SAE J1858
multipass cleanliness tests, shaker tests and static burst tests. A two-year field test encompassed
hydraulic oil, engine lubricating oil, and compressor oil filters on skid-steer loaders, agricultural tractors
and portable compressors. Over 14,000 filter hours were obtained on 14 pieces of off-road equipment
over the test period and 52 filter cleanings were performed. According to the company, oil analysis
showed that Eco-Clean filters provided cleanliness equal to or better than the original equipment filters that were used as a control, even after they were reused for multiple oil drain intervals.
The primary issue for any lube oil or hydraulic filtration system is how
effectively it reduces the amount of contaminants in the system. But a growing concern to manufacturers and users of mobile equipment are oil drain intervals and their related disposal issues.