I was asked recently to give a second opinion on the cause of failure of a hydraulic piston pump. The hydraulic pump had failed after only a short period in service and my client had pursued a warranty claim with the manufacturer.

The manufacturer rejected the warranty claim on the basis that the failure had been caused by contamination of … Read more

Hydraulic components are unique in that it is often possible to offset or balance hydrostatic forces to reduce loads on lubricated surfaces.

By reducing surface loading, the maintenance of full-film (hydrodynamic) lubrication is improved and therefore boundary lubrication conditions are less likely to occur.

Hydrostatic force is the product of pressure and area. Expressed mathematically: F = P x a. … Read more

Load-sensing is a term used to describe a type of variable pump control used in open circuits. It is so called because the load-induced pressure downstream of an orifice is sensed and pump flow is adjusted to maintain a constant pressure drop (and therefore flow) across the orifice. The ‘orifice’ is usually a directional control valve with proportional flow characteristics, … Read more