What filtration standard does a β value ≥200 signify for HYDAC filter elements?

In accordance with the multi-pass test standard ISO 16889, a β value ≥200 for HYDAC filter elements denotes the rated micron filtration specification. The beta ratio is calculated as: β = Number of upstream particles exceeding the specified particle size ÷ Number of downstream particles of the same size. A β value of 200 or higher corresponds to a filtration efficiency of no less than 99.5%, qualifying as the specification for high-performance precision glass fiber filter media.

Taking the 3 μm filter as an example, merely 0.5% of contaminants larger than 3 μm in hydraulic oil can pass through the medium, stably maintaining oil cleanliness at NAS 6~7 and providing reliable protection for precision components such as servo and proportional valves. This specification is commonly adopted in D and H series inline pressure filters, constructed with multi-layer graded Optimicron glass fiber media featuring deep dirt retention and moderate differential pressure buildup.

Compared with economy paper filters at β75 (98.67% removal efficiency), β200 filter media delivers superior filtration consistency and effectively prevents fine abrasive debris from penetrating into the hydraulic circuit. Low-beta filters are acceptable for ordinary return-line applications, whereas β≥200 elements are mandatory for precision hydraulic stations, wind power units and high-pressure metallurgical hydraulic circuits.

Even before reaching the service life based on differential pressure, broken seals or cracked filter media will render the beta rating invalid, allowing massive contaminant ingress and accelerated wear of hydraulic components. Hence premium NBR or FKM sealing rings are essential to sustain long-term stable beta performance.