If you’ve worked with hydraulic equipment for any length of time, it’s likely that you’ve come across a hydraulic system with cloudy oil. Oil becomes cloudy when it is contaminated with water above its saturation level. The saturation level is the amount of water that can dissolve in the oil’s molecular chemistry and is typically 200 to 300 ppm at 68°F (20°C) for mineral hydraulic oil. Note that if hydraulic oil is cloudy it indicates that a minimum of 200 to 300 ppm of water is present. I recently audited a hydraulic system with cloudy oil that was found to contain greater than 1% (10,000 ppm) water.… continue reading »
Why You Should Record Hydraulic Oil Top Ups
According to the National Oceanic and Atmospheric Administration (NOAA), more than 700 million gallons of petroleum products enter the environment each year. Around half of which is through irresponsible and illegal disposal. But hydraulic industry experts estimate that when it comes to hydraulic oil, between 70 and 80 percent of that lost to the environment is through leaks, spills, line breakage, and adaptor failure.
One of my Hydraulics Pro Club members, who is a maintenance planner for a large coal mine, recently told me his mine purchased 447,000 liters of hydraulic oil last year. It’s hard to believe planned hydraulic oil changes accounted for much more than a third of this volume.… continue reading »
Static Hydraulic Cylinder Pressure and Temperature
In The Hydraulic Troubleshooting Handbook I lay out a step-by-step SYSTEM for reliable and efficient troubleshooting. But there’s another prerequisite you won’t find in the job description: the ability to educate and convince the most ardent skeptics of your diagnosis – usually engineers with limited hydraulics knowledge. This story, sent to me by Joachim Renner, one of our members from Germany, is a great illustration:
“Our company supplied eight double-acting hydraulic cylinders for an auxiliary function on a tunneling machine. The cylinders had the following dimensions:
Piston diameter 140 mm
Rod diameter 90 mm
Stroke 600 mm
During machine commissioning we got a complaint that none of the hydraulic cylinders were holding pressure.… continue reading »