Valve that is in parallel with a hydraulic unit and that permits the pressure fluid to bypass this unit under certain circumstances. Example: Pre-loaded check valve that is in the secondary flow for a filter and that permits unfiltered medium to bypass the filter element if a stipulated pressure difference is reached in the filter (Figure B 27). However, as a result the effectiveness of the filter will be degraded (Figure B 28). This arrangement is a bypass check valve.Figure B 27: Bypass valve
Figure B 28: Effect of a bypass valve on the effectiveness of a filter
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