By Jim Fitch
Practicing Oil Analysis Magazine
Filtration has two primary objectives. The first objective is “protective”. This refers to creating a barrier to protect particle-sensitive machine components from the invasion of contaminants capable of causing sudden-death machine failure. Machines that have high mission criticality from the standpoint of safety, lost production and/or repair cost are good candidates for protective filtration. Such filters are located just upstream of sensitive components. Many components don’t require wear in order to fail, but they can experience critical loss of performance due to motion impediment and/or flow blockage caused by the intrusion of particles of a particular size and composition. Servo-controlled electro-hydraulic valves are examples of such components that benefit from protective filtration.