Based on my experience at least, electrostatic discharge in hydraulic systems is not a widespread problem. But for reasons I’ll explain in a moment, it may be on the increase. So it’s definitely something you need to be aware of.

As you probably remember from school science experiments, electrostatic charge is generated whenever there is friction between two bodies moving relative to each other. No real surprise then, that electrostatic charge generation occurs in hydraulic systems as a result of friction between the fluid and system components.

A common symptom of electrostatic discharge in a hydraulic system is an audible clicking noise as charge repeatedly increases and then discharges to a surface of lower voltage through sparking.… continue reading »

A recent client asked me to investigate and solve a recurring problem on a diving bell launch and recovery system. The system comprised a hydraulic power unit, a bell winch, an umbilical winch and a guide-wire winch.

To launch the bell, the guide-wire winch is used to lower a clump weight to the seabed. The guide wires prevent the bell from spinning during launch and recovery. And then the bell and its umbilical are launched using their respective winches.

After the divers have finished their shift on the seabed (usually 6-8 hours) the bell and its umbilical are recovered, followed by the clump weight.… continue reading »

One of our members wrote me with this question:

“I was subcontracted to remove a 30 GPM, 4000 PSI rated hydraulic pump from one plastic injection press and install it into a similar hydraulic system for the same company.

The hydraulic pump and prime mover are both beside and below (approx 12″) the bottom of the reservoir; a “flooded inlet” design. AND, except for the ball valve at the tank port, there are no other restrictions.

The customer insisted that I fill the pump’s case; I did so, but assured him that except for the hydraulic reservoir being empty, the pump would always have an adequate oil level.… continue reading »