Machinery Lubrication magazine published by Noria Corporation
Issue link: http://www.e-digitaleditions.com/i/544388
20 | July - August 2015 | www.machinerylubrication.com container supplied by the offsite oil analysis laboratory. The sample was collected immediately after shutdown. If it was not obtained within 30 minutes of shutdown, the gearbox outer shell and input shaft were manually rotated numerous revolutions before fl ushing the sample collection fi tting and taking the sample. After frequent oil sampling to establish baseline data, the sample frequency was initially set at quarterly and later updated to 500 hours of operation. An hour meter was also installed on the drive motor instrumentation. Representative used oil samples, as well as new oil samples, were collected, labeled with all pertinent data and sent to the oil analysis lab. Cleanliness targets were set at ISO 18/16/13. The new samples would provide a means of determining the physical prop- erties and additives within the oil. The lab's oil analysis test slate included a variety of standard tests such as ISO cleanliness, kinematic viscosity at 40 degrees C and 100 degrees C, water by Karl Fischer, acid number and elemental spectroscopy. All of the oil analysis reports and recom- mendations received from the lab were closely reviewed to monitor the oil's physical properties, contamination and/or wear metals. Extending Oil Drains The oil was not replaced at the manufacturer's suggested one-year runtime interval because the oil analysis reports continued to be favorable. ISO cleanliness was diligently maintained through offl ine kidney-loop fi ltration using micro-glass fi lters. As the two-year maintenance interval approached, there was no data-driven reason to replace the gear oil, let alone to exchange the gearboxes. The original equipment manufacturer (OEM) was contacted to inquire whether exchanging the gearboxes was still A two-stage planetary gearbox Oil viscosity at 40 degrees C from 2007-2013 Water by Karl Fischer from 2007-2013 Acid number from 2007-2013 A 300-horsepower, AC-induction motor and bowl drive assembly 300 250 200 150 100 50 0 2008 2009 2010 2011 2012 2013 V40 CENTISTOKES 2008 0 50 100 150 200 250 300 350 2009 2010 2011 2012 2013 PPM KF_PPM 2008 1.2 1 0.8 0.6 0.4 0.2 0 2009 2010 2011 2012 2013 TAN MG_KOH_G