Experience is the key element
We have already mentioned that lab technician experience is the key element in effective data interpretation. Equally important is the experience of the maintenance people in taking representative samples, labeling them properly and getting them promptly to the lab for analysis. But perhaps the most critical aspect of experience is with the lubrication engineer or maintenance manager himself. It is his final judgment that determines what equipment will be sampled, at what frequency, and what tests are to be run. Ultimately it is his recommendation that will shut down a piece of equipment, whether it is for a simple repair or extensive overhaul.
Commitment, credibility and common sense
The ultimate value of oil analysis, however, is a combination of commitment, credibility, and common sense. An operator must be committed to oil analysis to be sure that representative samples are taken at regularly scheduled intervals and promptly mailed. The lab selected to do the analysis must have a credible reputation for speed, accuracy and experience. The reliability of their recommendations is essential to the cost/effectiveness of the overall program.
And throughout the entire process common sense is most important. Use common sense in selecting which pieces of equipment are to sampled, at what interval, and for what types of testing. The most cost/effective programs sample only critical equipment, at a minimum of 3-month intervals, and analyze only for the properties that are meaningful.
And use common sense when the data and recommendations are returned. If a system is to be re-sampled, make sure that it is done promptly. If a system is to be watched for a developing problem, be sure that someone takes a look for the obvious signs of trouble such as leaks, vibration, plugged filters, excessive consumption or missing filler caps.
You are paying for advice . . . be ready to use it
By all means, when the analysis recommends shutting down equipment, do so. If you find it is simply impossible to shutdown the equipment, you can always review the recommendations with the lab director and see if a compromise can be worked out. One farmer was told to shutdown his harvester because there was a serious coolant leak into the engine crankcase oil. Continued operation with high levels of coolant contamination would have almost certainly ruined his engine, resulting in considerable replacement cost. Yet the equipment was in the middle of a critical two week harvest, and just couldn't be taken out of service. The compromise . . . Change the oil and sample the system every day. The daily analysis indicated that the leak wasn't getting any worse, and changing oil everyday prevented serious engine damage. At the end of the two week harvest the cooler was repaired with only minor parts and labor costs. Remember you can always change labs if you find out that they are "crying wolf" too often, but it makes little sense to pay for the experience of a lab, and then not use it.
We hope that you will benefit too
By one estimate only three out of every ten maintenance operations use oil analysis at all, and of those three, only one uses the technology to its full advantage. If your operation is one of the three we hope that this article has helped you see where you can make your current oil analysis program more efficient. If your maintenance program doesn't currently include oil analysis, we hope that you are now more familiar with the technology, and better able to decide if it would be helpful in your particular operation.
The above article is copyright 1981 by Fluid Marketing Corp.
