Hydraulic pumps

A pump does not create pressure, it delivers flow: the pressure comes from the resistance that flow meets. It is therefore sized on displacement, drive speed and the maximum pressure the circuit will take.

The gear pump covers most mobile applications: rugged, tolerant, inexpensive, and graded in groups of increasing size (1 to 4). The axial piston pump goes higher in pressure and, in variable-displacement form, delivers only what is asked of it, which keeps heat build-up down. The vane pump is still favoured on fixed power units for its quiet running.

• To replace a pump, note the flange bolt centres, the spigot diameter, the shaft type, the ports and the direction of rotation.
• The suction line decides how long a pump lasts: generous bore, short run, clean strainer. A pump that cavitates wears out very quickly.
• A pump that is noisy or running hot is a symptom, not a lost cause: check the suction side, the oil level and the viscosity before replacing it.

We identify your pump from the unit you bring in, and supply the coupling, bell housing and pipework that go with it.