Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/1206285
www . machinerylubrication.com | January - February 2020 | 13 Figure 13. Vibration spectrum on the gearbox after intervention had the ability to reveal issues before other predictive maintenance tech- niques, as alarms would appear in oil analysis reports that did not manifest in the other techniques. For example, in the oil analysis results for a soybean elevator reducer, the iron content increased from 65 to 527 parts per million (ppm), while the chromium value increased from 0.10 ppm to 0.83 ppm. is was a strong indication of bearing wear. By analyzing the vibration data for the same month, plant personnel found that the values were still within accept- able limits. However, vibration analysis was able to more accurately identify which element was being worn. Although the vibration results were not alarmed, the trend curve revealed the values were rising. Figure 9 shows that these values sounded the first alarm on July 15, 2019, but were still accept- able compared to the oil analysis results, which already indicated high severity. Note also that the chromium value increased from 0.10 ppm in previous samples to 0.83 ppm. is suggested some bearing deterioration. In the same report, other important signs could also be seen, such as a reduction in phosphorus as a result of the increase in iron. A similar situation occurred with one of the plant's lift gearboxes. In this case, the issue also was detected first through oil analysis and only later through vibration analysis. Figure 11 shows the trend of increasing iron levels from the oil analysis results. Meanwhile, the gearbox's vibration analysis results for the same month were normal. It wasn't until more than a month later that an increase in the vibration values indicated an input shaft bearing failure. With this information in mind, plant personnel decided to inter- vene in the machine and replace the damaged oil and bearing. e rolling elements of the changed bearing attest that both techniques were successful. After the oil and bearing replacement, the vibration analysis showed no defects. e plant has seen encouraging results from combining oil anal- ysis and vibration analysis. ere have been fewer breakdowns and an increase in productivity. Faults are managed and interventions aligned with production planning to reduce downtime. Machine components and the lubricating oil are changed only when necessary to maximize their lifespan. e plant's balanced equipment vibrates less and consumes less energy. Components like bearings and seals are even lasting longer. Oil analysis and vibration analysis have proven to be effective tech- niques for monitoring the condition of assets. While many studies have shown that oil analysis can provide an earlier warning of potential failures, the best results occur when there is an integration of these two techniques, making them both indispensable in today's maintenance programs. ML ML PENETRATES. LUBRICATES. PROTECTS. Unlike ordinary rust solvents, Penetro's exclusive oil-based formulation not only breaks through rust, it coats metal surfaces with a lubricating film that won't wash off. • Triple protection against rust. • Triples the life of hoist chains and sprockets. • Prevents thread stripping. schaefferoil.com 314.865.4100