Gear pumps are a type of rotary positive displacement pump, meaning they pump a constant amount of fluid for each revolution. Gear pumps transfer fluid by gears coming in and out of mesh to create a non-pulsating pumping action. Gear pumps are able to pump at high pressures and excel at pumping high viscosity liquids efficiently.
There are no valves in a gear pump to cause friction losses and also high impeller velocities, with resultant friction losses, are not required as in a centrifugal pump. Therefore a gear pump is well suited for handling viscous liquids such as fuel and lubricating oils. Gear pumps are not suited for pumping solids and abrasive liquids.
