While doing some fact checking for a consulting job, I had cause to review Australian Standard AS 2671-2002; Hydraulic Fluid Power-General Requirements for Systems. This Australian Standard is basically the International Standard, ISO 4413 with some amendments based on the local advisory committee’s input.

One of these amendments has to do with pump suction strainers. Section 8.3.3 of ISO 4413:2010, … Read more

One of the advantages of variable-displacement pumps with hydraulic or electro-hydraulic displacement control, or load-sensing control, is their low standby pressure. Meaning, when pump output isn’t required, the pump ‘stands by’ at a relatively low pressure, and usually at zero flow (other than that necessary for the make-up of internal leakage).

From an efficiency (heat-load) perspective, the lower this standby … Read more

One of our members writes:

“We have a simple hydraulic system: pump and 4 double-acting cylinders. Most of the oil between the directional control valve and cylinders ‘shuttles’ back and forth in the lines without returning to tank. The manufacturer of the system, Rexroth, tells me there is never a need for bleeding air from the system. How can this … Read more