
Variocap as excess pressure protection
Safe operation with the variocap
The variocap is a simple and effective way to install protection from excess pressure.
The force produced by the pumping pressure acts on the pump cover, which consists of an outer ring and an inner, spring-loaded plate. As long as the spring force is greater than the pressure, the plate stays in the sealed position flush to the pump chamber. If the pressure rises above the set spring force, the plate moves axially and allows the pumped medium to flow back from the pressure side to the suction side. When the pressure subsides, the gap then closes again.
The complete variocap is hermetically sealed by a built-in elastic seal diaphragm and the other moving parts are untouched by the medium.