In brief
A vane pump is a positive displacement pump in which radially movable vanes in an eccentric cam ring form pumping chambers of varying size.
Contents
What is Vane pump?
A slotted rotor turns eccentrically in a cam ring. Vanes sit in the slots and are pressed outwards against the ring by centrifugal force or pressure. Chambers form between each pair of vanes, enlarging on the suction side and shrinking on the discharge side. Vane pumps run quietly and smoothly and are valued in machine tools, plastics machinery and presses.
In fixed displacement pumps, the displacement is fixed; double-stroke versions with an oval ring balance the bearing forces. In variable displacement pumps, the eccentricity of the ring is changed, often via a pressure compensator, so that once the pressure is reached the pump only covers leakage losses. Key parameters are displacement, pressure, speed, direction of rotation, controller version and mounting. Rotary vane vacuum pumps work on the same principle.
Vane pumps are sensitive to contamination and to viscosity that is too low. Wear on vanes, ring and side plates reduces output; spare part kits with rotor, vanes and ring are common. Before installing a replacement pump, the cause of the wear should be clarified, usually contamination or the wrong type of oil.
In practice: maintenance and procurement
For replacement or repair, the displacement, pressure range, direction of rotation, controller type, shaft end, flange and ports are needed. For worn pumps, it should be checked whether a cartridge kit is sufficient or the complete pump has to be replaced.
Synonyms and abbreviations: rotary vane pump · variable displacement vane pump · sliding vane pump · vane-type pump
Frequently asked questions
What is the advantage of a vane pump?
Vane pumps work with low pulsation and a low noise level. As variable displacement pumps, they automatically adapt their displacement to demand, reducing energy consumption and heating, for example in clamping hydraulics on machine tools. In addition, many series can be repaired by replacing an inner cartridge.
What is the difference between a vane pump and a gear pump?
Both are positive displacement pumps. Gear pumps are simpler, more tolerant of contamination and mostly designed as fixed displacement pumps. Vane pumps run more quietly and can be built as variable displacement pumps, but are more sensitive to dirt and viscosity. The choice depends on pressure, noise requirements and control needs.
What information is needed to replace a vane pump?
Important are the displacement, maximum pressure, fixed or variable version with controller type and setting, direction of rotation, shaft end, mounting flange and ports. The complete type designation from the nameplate usually contains these features in coded form. For multiple pumps, each stage must be specified individually. A photo of the shaft and ports is also helpful.