An air cleaner is a vital component of the air intake system on all combustion engines. Engines can be required to operate in a variety of environments, from relatively clean ones, such as many marine applications, to those with extreme levels of dust often found in mining and construction. Regardless of the environment the engine operates in, or the size of the engine, it only takes a surprisingly small amount of dust to be ingested through the air intake system to effectively destroy an engine. As little as 300 grams, or half a cup of dust will have a big impact on the life of even the largest engine. Therefore, we must ensure the incoming air is as clean as possible.
The air cleaner housing contains one or more filters to remove contaminant from the incoming air, promoting long engine life. The filter uses a media which can be made from a number of different materials, the most common of which is cellulose, or paper. All media types are designed to capture the contaminant and prevent it passing into the engine. A good quality cellulose filter will do this with a minimum of 99.9% efficiency.
When cellulose media is used, dust is captured in the pores between the cellulose fibres. As the amount of dust accumulates, the pores gradually fill and the filter actually increases in efficiency. Eventually however, the contaminant builds to a point where the filter reaches its holding capacity and it becomes too hard for the engine to draw air through the air cleaner. This is the maximum restriction level, and the point at which the filter needs to be replaced with a new one.
Technology allows us to produce filters that will last longer and work better than standard cellulose filters which means lower operating costs, longer periods between services and higher performance levels.
Some filter media, such as Donaldson Ultra-Web® media, as examples of technology at work. The media uses cellulose media as a frame work, with proven strength and reliability, but then has a super fine web of nanofibres bonded across the top surface. The nanofibres are much smaller than the cellulose fibres and are able to capture even smaller contaminant particles. Significantly, the contaminant is captured on the surface of the filter media rather than within the media. The natural pulsing effect of the air being drawn into the engine actually shakes off dust as it builds up on the surface of the filter so the filter literally 'self-cleans', and as a result, ill have a much longer life than a conventional cellulose filter.
An added advantage is the initial efficiency of the Ultra-Web® media, at 99.98% is also significantly higher than a standard cellulose, keeping even more dust away from your expensive engine.
Most of the dust that gets past an air cleaner does so when the filter is removed, so it makes sense that the less often the filter requires replacing, the less chance dust has to reach the engine.