Evaluating a Customer’s Circuit Before Trouble Shooting

By Robert Sheaf, CFPAI/AJPP, CFPE, CFPS, CFPECS, CFPMT, CFPMIP, CFPMMH, CFPMIH, CFPMM, CFC Industrial Training.

I have been teaching hydraulics since 1980 and found that many good maintenance technicians cannot determine what pressures should be on the attached circuit. How well will you do?

Note: The actual drawing shown does not show the counterbalance bypass check that was built into the valve used. (Errors and omissions like this are common with drawings we are given to trouble shoot a problem.)

First: What would you expect the approximate pressure to be on gage “A,” if only the electric motor and Sol. 1B were energized?

Second: If the system were turned off with the ram fully retracted, would the ram drift down?

Third: If the ram were held in the fully retracted up position with the motor running and Solenoid 2B energized, what would gage “E” read?

See Solution

Robert Sheaf has more than 45 years troubleshooting, training, and consulting in the fluid power field. Email rjsheaf@cfc-solar.com or visit his website at www.cfcindustrialtraining.com. Visit fluidpowerjournal.com/figure-it-out to view previous problems.