When a pump is subjected to a restricted inlet condition as in the case of units incorporating a dry valve setup,
cavitation of the lubricating fluid will occur if an unrestricted path back to the oil reservoir is unavailable at the
outlet of the pump. To greatly reduce the occurrence of cavitation, Permco has developed a by-pass control that
gives the lubrication flow a direct, unrestricted path to the hydraulic reservoir. Unlike other manufacturers
controls that provide the same function, the Permco design is the only one available that is integral to the pump
itself and provides a positive closure (shut off) when the work circuit is activated. In doing so, all flow that would
have been by-passed to tank (as in the case of pressure compensated controls that bleed a given amount of flow
continuously through the entire work cycle), is directed to the working circuit providing full power to the system.
Because the by-pass control is integral to the pump, all that is required for installation is a 3/8" diameter hose
with one end connected to the 3/8" NPT port located on the side of the port end cover and the other end
connected to the hydraulic reservoir.