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What are Aircraft Hydraulic System Filters?

Hydraulic systems are crucial for the standard operations of many modern aircraft, serving to create the force necessary to manage flight surfaces, landing gear assemblies, and other such systems that are commonly used in each flight operation. In order for hydraulic systems to function as intended, they must be able to effectively control the flow and compression of fluids within an enclosed space, and as such, fluids and fluid system parts need to be kept free of any contaminates or substances that would result in the malfunction or failure of the system. To keep a hydraulic system clean, special hydraulic filter components are relied on.

Filters are fairly simplistic devices, serving as screening or straining components that remove any foreign particles from fluid as it passes through the filter. Foreign debris can come in many forms, often resulting from dirt that enters the system, metal particles that come from hydraulic components that are facing wear, and more. While some particles may be extremely tiny, they can still cause ample damage to units and parts over time. Additionally, hydraulic system components often have a tight tolerance for foreign matter, making it very important that filtration is upheld for peak performance and operation.

Rather than a single filter cleaning the entire system, multiple filters may be situated in a variety of areas where there is a need for protection. Generally, these locations include the pressure line, return line, and reservoir. Furthermore, the filter may come as a module including the filter alongside other components in a single housing. A majority of hydraulic filter components are of the inline type, those of which include a head assembly, bowl, and element for their design. The head assembly itself is connected to the aircraft structure, and a bypass valve is present for routing hydraulic fluid around the filtration element in the instance that it becomes clogged with foreign debris. Meanwhile, the bowl houses the element, preceding it against the head.

The element is what filters out unwanted substances, and it may come in a number of types based on the design of the unit. Generally, the most common variations are micron, porous metal, and magnetic types. With a micron element, specially treated papers are used for construction, necessitating regular replacement of the filter after it is used. Meanwhile, porous metal and magnetic filter elements can be cleaned between uses, only being replaced when the service life is exceeded based on time or health.

Filters are fairly easy to maintain, generally only requiring one to either clean or replace the unit. Utilizing manufacturer instructions, one can best determine when the filter should be replaced, as well as how often maintenance should be conducted. Even with cleanable elements, any damage or issue should warrant replacement so that clogs or other issues do not occur. Once the filter element is replaced, the hydraulic system will need to be pressure tested to guarantee the intactness of the filter assembly. For any hydraulic system component need that you may have during maintenance, we recommend that you rely on Civil Aviation 360 for procurement.

Civil Aviation 360 is a premier purchasing platform belonging to the ASAP Semiconductor family of websites, and we offer customers access to an unrivaled inventory of items that have been sourced from top manufacturers across the globe. With over 2 billion items ready for purchase, we encourage you to take the time to explore our expansive website. To request quotes on any items that we carry, or to receive a customized solution on parts that are not available, send us a completed RFQ form at your earliest convenience. With your provided information, our team will create a quote that fits your needs and present it to you in just 15 minutes or less.



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