Standard_Parts_Catalogue

Page 1613 | 3.5 Controlling, Venting, Sealing of Liquids and Gases 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 GN 663 Breather Caps continued Air flow rate [l/min] in reliance on the pressure difference Δp [mbar] container / outside space with filter (40 µm): without filter: Type with splash guards (Identification no. 1 and 2) Air flow rate [l/min] in reliance on the pressure difference Δp [mbar] container / outside space with filter (40 µm): without filter: Type without splash guards (Identification no. 3 and 4) Breather caps GN 663 are normally used in larger oil reservoirs which must be ventilated and whose level changes rapidly. The latter requires a high air flow rate during breathing / ventilating (Breather caps GN 552 → Page 1608 are usually sufficient for smaller containers and gears). If agitated, there is the risk that oil will leak. With proper- ly aligned and shaped splash guards (see schematic dra- wing), these breather caps prevent the oil from leaking without substantially disrupting the ventilation / breathing process (pressure compensation) The splash guards can be left out if their function is no longer needed or if a maximum air flow rate is desired. A filter is used to protect the oil from outside pollution (dust). The filter is made of PU foam with a filtration of 40 µm. The filter in these breather caps has a large volume for longer service life, i.e. it does not clog up too quickly. Description of function