Where to Take a Hydraulic Oil Sample and When

hydraulic oil drumFrom a predictive maintenance perspective, there is little real benefit from taking an oil sample directly from the hydraulic tank. Sure, an oil sample taken from the tank can be used to establish the cleanliness of the hydraulic fluid, and the condition of its base oil and additives.

But these days, most hydraulic systems feature a return filter, and so … Read more

The Hydraulic Tank Size Dilemma

how to heat hydraulic oil safelyWhen it comes to sizing a conventional hydraulic reservoir, my motto and advice is the bigger the better. Because the greater the tank volume the longer the dwell time the oil has to give up contaminants – particles, water and most importantly of all, air. Sure, particles and water can and should be filtered out of the oil. Air can … Read more

The Effect of ‘Silt Lock’ on AC Solenoid Valve Coils

Hydraulic Solenoid Valve (Bosch Rexroth)

In true AC electric coils, the resistance or impedance of the coil is lowest when the solenoid is open, i.e. when the plunger is out. Impedance increases as the plunger is pulled into the closed position. As a result, the current draw of an AC solenoid is highest when the solenoid is open (plunger out) and lowest when the solenoid … Read more