Several years ago, Westinghouse recognized that it could achieve savings by utilizing many of the condition-based monitoring techniques. Through a pilot maintenance optimization program in a powerhouse plant, the company identified that an oil analysis program would eliminate time-directed oil changes. One department purchased oil analysis screening equipment and obtained a volunteer maintenance mechanic to support the budding oil analysis program.
The
company learned that education and training were essential to understanding
the benefits of oil testing; only knowing how to test was not enough. Initially,
the company faced more questions than answers. What seemed simple and tangible
was actually more complex. To obtain value from oil analysis the company needed
a solid understanding of lubrication fundamentals, proper sampling techniques,
the equipment analyzed and an idea of what answers they were seeking from the
test data.
After an education in oil analysis, testing became more meaningful. It became more important to obtain oil samples correctly. The oil sample needed to represent a true picture of what was actually lubricating the machine surfaces. After developing proficiency with some simple oil tests, interest grew in knowing the origin and point-of-entry of contamination found in the lubricants. Although it did not have the capability to produce a ferrogram, the company did try to determine if machine reservoirs were contaminated or if the contamination was present in the new oil. The reservoir of one machine was drained and refilled several times with fresh oil only to discover the oil was as contaminated, if not more contaminated, than before. A hand pump pressure washer with mineral oil was used to clean the reservoir before adding new oil. After starting and stopping the machine, the new oil was still contaminated. It was only after filtering the reservoir oil that the desired oil cleanliness level was reached. The onsite lab permitted the company to quickly evaluate and turn around the results of multiple tests to ensure clean oil.
The time and effort spent with this one machine was of great significance to Westinghouse. The passion exhibited by maintenance personnel wanting to learn about and achieve oil cleanliness strengthened and improved the maintenance and oil analysis program. Several filtration carts have now been acquired to service many oil reservoirs such as the one described above to preserve the useful life of the oil and reduce waste oil generation. Several maintenance practices have been revised for the handling and dispensing of new oils within the departments. Many machines now have quick-connect fittings so that reservoir oil can be circulated, routine samples drawn and the oil filtered to remove contaminants.
The benefits of this program included reductions in new oil consumption, reductions in waste oil handling, extension in oil useful life, less wear on internal operating components and reduced downtime (less overhauls). Dispensing facilities have been established to ensure clean oil is actually used in the field. When new oil arrives and is found to have an unacceptable level of cleanliness, it is filtered and cleaned before put into use. Desiccant breathers have been added to oil storage drums to prevent moisture infiltration and contamination.
The company’s next goal is to develop and enhance wear particle evaluation and improve root cause assessment. Vibration analysis and oil analysis are practices now used to make judgments regarding equipment and lubricant health, and to provide confirmation of these judgment calls. The company sees the importance of identifying contamination to determine where improvements need to be made. Other areas are currently being explored as a result of the onsite oil analysis program. These include testing for coolant and fuel oil leakage in diesel engine oils, evaluation of hydraulic systems, consolidation of plant-wide oil and greases, establishing oil supplier cleanliness standards, procedures for onsite lubricant storage and handling, standardizing the techniques and components used for oil sampling, correlating oil contamination to ultrasonic and frequency response, extending oil and component life and analysis of transformer oil.
Although not completely recognized in the early stages of program development, there are benefits to bringing oil analysis onsite. The investment made for the equipment and the tedious tasks maintenance incurred while evaluating lubrication practices has been well worth the expense. Many of the larger machines have gone several years without major overhauls or oil changes. As the technicians become proficient in oil analysis testing, analysis cost per sample drops. The company pinpoints and performs only those oil tests required to determine root cause for equipment or oil related problems. The existing networked PdM software supports trending and displays oil and vibration data to all groups. Onsite oil analysis is highly recommended as an excellent investment for your maintenance personnel and reliability programs.
