In the food processing industry, extra care is taken to ensure hydraulic oil does not find its way into the product. The circuit shown is one that had air causing the cylinder to drift, creating a problem with the autocycle sensors. Notice the extra rod-gland drain line. It lets operators see if the seal was leaking and replace it before it became a problem. The long lines with 50-psi check valves were used to make sure oil leaving the cylinder returned to the tank for filtering and fresh oil was making it to the cylinder. The production line was on the first floor with the power unit in the basement
Recently, the customer had a problem with the rod-end meter-outflow control getting so hot the paint was peeling off it. The maintenance crew was new to this part of the plant and did not know much about the original design. After a new flow control did not fix the problem, their next solution was to install a heat exchanger.
Any idea what caused the overheating?
What’s the Problem?
Think you know the answer to this month’s troubleshooting problem? Then email your answer to [email protected] (put “March Troubleshooting” in the Subject line.) All correct answers received by April 30 will be entered in a random drawing. The winner will be mentioned in a future column.
Solution to Last Month
Ink Mixing Machine’s rpms Fluctuate Out of Limits
The ink mixer speed problem was caused by a pump and/or motor that had excessive wear.
As the dry chemicals were added, it required additional pressure to turn the mixing blades which in turn increased the leakage in the pump/motor units. As liquid was added, it thinned out the mixture, lowering the pressure which caused the leakage to reduce increasing the speed. Typically, when there is wear-and-tear in hydrostatic system, both pump and motor should be reconditioned or replaced.
Gregory J. Palet of Minocqua, Wisc. got the February solution first. Congratulations!
Robert J. Sheaf Jr., is founder and president of CFC Industrial Training, a division of CFC Solar, which provides technical training, consulting and field services to any industry using fluid power technology. Visit www.cfc-solar.com for more information.
