Machinery Lubrication magazine published by Noria Corporation
Issue link: http://www.e-digitaleditions.com/i/680544
BACK PAGE BASICS 56 | May - June 2016 | www.machinerylubrication.com 39% of lubrication professionals do not maintain precise oil levels in the sumps and reservoirs at their plant, according to a recent survey at MachineryLubrication.com aerate the oil, which changes the viscosity, speeds up oxidation and uses up additives. If the machine is run in these conditions, the lubricant film strength weakens, boundary conditions form and machine damage may occur. Causes of Incorrect Oil Levels Leakage is probably the No. 1 cause of a low oil level. Many points on equipment can suddenly or gradually fail. Seals may pres- surize and allow oil to leak. Gaskets can fail due to age or excessive heat. Remember, everyone has leaks of some sort with their equipment. It's how you deal with these leaks and move forward that will determine if machine damage will occur. When leaks are discovered, they should be categorized by priority, tagged and entered into the maintenance system for repair or monitoring. Typically, employees will notice a small leak and ignore it or top off the oil to the correct level and go about their day. Of course, small leaks turn into bigger leaks that can be more difficult to remedy. Even if a leak remains small, over time there will be increased lubricant consumption, disposal and labor. Another cause of an incorrect oil level is misunderstanding the recommendations from the original equipment manufacturer (OEM). Sometimes it's not clear where the level should be and may depend on how you look at it from different positions and angles. The OEM manual should have diagrams and instructions on where to set the oil level in your equipment. If you are still confused as to where the level should be, call the manufacturer and ask. It is crucial to get it right. If you fail to maintain the correct oil level from implementation, internal damage can happen immediately and shorten the life of the equipment. The oil level should also be clearly marked for field inspection. I've often seen oil level indicators with no markings to specify where the level should be main- tained. This is especially important with column-level indicators where the oil level can range 6 to 15 inches depending on the length of the indicator. Remedies A number of things can be done to ensure the right oil level is maintained in your equipment. As mentioned previously, the oil level should be determined before the equipment is turned on for the first time. The best time to decide on the appropriate oil level is when the equipment first arrives at your facility. This is when all the deci- sions are made on how to retrofit the equipment for your reliability goals. Once the correct oil level is identified, it must be clearly marked in the field. This can be achieved with upper and lower limits on the column indicator. Use a mate- rial that is durable enough for the environment. Also, record the lubricant volume and other relevant notes in a database. Develop procedures for everyone to follow, including what to do if a low or high oil level is discovered. Reporting a problem at this phase can help with troubleshooting later for a root cause analysis. Not all problems show up right away within your equip- ment. It may take months or years before a small defect becomes a big issue. In addition, address when the oil level should be read. When machinery is opera- tional, the oil level usually reads less. This can lead to false readings and added work. I've seen situations when an oil level was topped up to the upper limit while the machine was running. When the equipment was shut down, the oil level was past the upper limit. Don't forget to record all top-up volumes. What might be a small leak today could turn into a large leak tomorrow. All leaks should be reported and prioritized. Finally, train your personnel. Checking a level indicator might seem like a small task, but it is crit- ically important for the reliability of your machinery. While not every piece of equipment will self-destruct because the oil level is higher or lower than it should be, there are machines that can be expected to fail based on the oil level. In my view, every machine should be treated with the same expectations of controlling the oil level and making sure it is well-maintained. About the Author Garrett Bapp is a technical consultant with Noria Corporation, focusing on machinery lubrica- tion and maintenance in support of Noria's Lubrication Program Development (LPD). He is a certified lubrication specialist through the Society of Tribologists and Lubrication Engineers (STLE) and holds a Machine Lubrication Technician (MLT) Level II certification through the International Council for Machinery Lubrication (ICML). Contact Garrett at gbapp@noria.com.