Hydraulic filter element that is discarded

BACKGROUND

A filter is a screening or straining device used to clean the hydraulic fluid and keep foreign particles from remaining in the system. The element may be a micron, porous metal, or magnetic type. The micron element is made of a specially treated paper and is normally thrown away when removed, while the porous metal and magnetic elements are designed to be cleaned by various methods and replaced in the system. Filters using the micron-type element should have the element replaced periodically according to applicable instructions, and because reservoir filters are of the micron type they must also be periodically changed or cleaned. When replacing any element, be sure there is no pressure on the filter bowl, wear protective clothing and a face shield, install an element of the proper rating, and pressure test the system afterward to confirm that the sealing element in the filter assembly is intact.

STUDY TIP

Tie the element material to the maintenance action: paper means replace, metal means clean and inspect closely for damage.

KEY POINTS

• Micron (treated paper) elements are discarded when removed.
• Porous metal and magnetic elements are cleaned and reused.
• After element replacement, relieve bowl pressure first and pressure test the system afterward.

SOURCES

• sources/ama-airframe/ch12.txt "Maintenance of Filters"
• sources/ama-airframe/ch12.txt "Filters"