what are Hydraulic filters and What is their function

• Any hydraulic equipment Or Engine, to function smoothly and for peak performance it’s hydraulic OR lubricating oil has to be contamination free.
• From studies , it is revealed that more than 70% failures of engines OR hydraulic systems ,are due to Contamination in the systems.
• Contamination in generated due to wear and tear of moving parts due to friction .To prevent systems Or engines from failure, filters are required .
• The filters which are used in Hydraulic circuits are called hydraulic filters and one used in engines, turbines etc . are lubricating oil filters.
• Similarly there ate fuel filters which are used to prevent contamination to enter engine Or turbine and spoil working of it.
• Filters are designed to prevent; to remove particles that are not supposed to be part of the fluid. There are many different kinds, too, so it is imperative that you choose the kind that is designed for your particular needs. You can get Hydraulic Filters manufacturers worldwide.

Bag Filters

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• These are most common type of filter. This consists of a cloth or synthetic material formed as simple bag and mounting arrangement at the top of it.( Like we stitch handles on top of carry bags.).
• Through this bag that the hydraulic fluid is passed through, which then catches all of the solid contaminants, as they get caught in the filter.
• These types of filters are most common in industries as they are primitive and contamination can be removes from time to time.. They are usually very inexpensive and easy to clean or change.

Screen Filters

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• Metal Screen filters are similar to bag fabric filters, except very fine metal wires instead of cloth thread are used.
• These are then woven together, much like fabric is, to create a metallic cloth. Different arrangement of weaving is available for different strength of metallic cloth and different size of opening of mesh is available in the market.
• They can be made from any fine metal wires . instead of cloth in bag filters, the engineers can design the filter from this metal fabric as per micron rating required for the system. This micron rating slected depends mainly of the size of the particles of contamination.

Magnetic Filters

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The magnetic filters are specially used where iron particles are generated as contamination of engines . They use specially charged plates Or mangentic rings, which have been magnetized. Any iron particle that have become entrapped in the fluid will be picked up and held by these types of filters,But it doesn’t prevent dirt and other non-iron particles of fluid.

Filter Construction

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There are different types of filters are available in the market to choose from.. Depending upon it”s location in the systems , they are called inline, return line, Duplex , offline etc.

• The most popular filter is called in-line arrangement which allows the inlet and the outlet valves to sync up directly with the filter. This to prevent bad function of valve itself.
• The other type of arrangement is called off-line, means the filter is not part of the hydraulic system’s main loops.
• If the oil is to be cleaned before it enters tank , return ine filters are used . they are generally tank top mounted.
• Duplex filters are used where there is requirement of changing filter element while the systems is still on and working.
• They are consists of two different filter bowls combined together through a change over valve at the center.
• All other factors like pressure, flow rate , pressure drop allowed, size of contamination generated , micron rating required by system etc are important for right selection of filter for the system.