Typical industrial applications involve closed circuits of materials such as hydraulic fluid, cooling water, coolants, lubricating oil, refrigerants, etc. The task of filters is to keep the circuit clean and accordingly maximizing service intervals and lower costs.
- Maintaining purity classes
Modern components of a hydraulic system can be significantly impaired or even damaged by particles: Valves, pumps, sensors, bearings and nozzles require a fluid of a specific purity to function smoothly. The filters must ensure that a specific cleanliness class is reliably maintained. Manufacturer of components sometimes require that this be guaranteed. To achieve this, the utilized filter material must possess β value > 75. In addition, the filter elements must be processed flawlessly so that not a single particle above the specified size will pass through the filter. - The filtration approach
Keeping a circuit clean involves more than just the individual filter's reliability; it is a function of the overall filtration approach.
In a system consisting of a tank, pump and consumer, the working filter is in the downstream line of the hydraulic circuit to separate particles generated by abrasion, etc. This prevents them from entering the connected tank, and the downstream pump is reliably protected from contamination. Other filters follow the pump, are in the tank bypass, the tank vent, or in the pump intake area. An optimum filtration approach for a hydraulic system in mining can be found here: filtration concept. - Regenerability and long service life
Stainless steel filters have superior mechanical strength and are frequently very easy to clean. The possibility of cleaning such filters increases their lifetime and saves you the cost of procuring new filters. One special application is the so-called back flush filter system where the filter cake is freed from the filter elements by back-flushing in the housing without removing the elements, and the contaminated liquid is removed from the system.
