Hydraulic systems filter location

Strainers are used primarily to catch only very large particles and will be found in applications where this type of protection is required. Most hydraulic systems have a strainer in the reservoir at the inlet to the suction line of the pump. A strainer is used in lieu of a filter to reduce its chance of being clogged and starving the pump. However, since this strainer is located in the reservoir, its... 

A pressure line filter is located on the delivery side of the pump and is thus exposed to full system pressure. It will protect the following system from pump-generated or pump-passed contaminants, but not from any contaminants generated within the hydraulic system downstream of the filter. 

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