Sensor detects piston position in accumulators…(Hydraulics & Pneumatics Magazine)

“Whether they use a piston or a bladder, accumulators are all about precharge pressure. When sizing an accumulator, specifying the correct volume and precharge pressure can mean the difference between a system that runs smoothly and efficiently, or one that is plagued with problems. Mac Stuhler, vice president at Control Products Inc., East Hanover, N. J., explained that monitoring the precharge pressure of a bladder accumulator is fairly straightforward: install a pressure transducer to detect the pressure of the precharge gas in the bladder.”

Because piston seals are dynamic, they are subject to wear and eventually will leak. This can cause the piston to drift, so even though a pressure transducer may indicate the correct pressure, the piston may not be where it should based on the pressure..”

“…sensor works on the gas or fluid side of the piston
“…Control Products introduced three sensors that detect the absolute position of pistons in accumulators (and hydraulic cylinders, too)

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