Embracing Precision Lubrication At UOSA

The Upper Occoquan Service Authority (UOSA) is an advanced wastewater treatment plant near Washington, D.C., with a permit to treat 54 million gallons of sewage per day. The facility, which came online in the late 1970s, receives residential, commercial and industrial waste streams and returns clean water to the Occoquan Reservoir.

Approximately 15 years ago, UOSA management determined that it was imperative to update its organizational approach to asset management. In addition to a review and update of the master equipment records, there would be a more scientific approach to maintenance. A new enterprise asset management (EAM) system and a computerized maintenance management system (CMMS) were implemented to reap the benefits of greater integration of maintenance and financial matters.

Improving Lubrication

One of the first maintenance areas studied was lubrication. The CMMS had listed lubricants but not in a user-friendly way. There were some lubrication codes that specified up to three different lubricant types. An introductory course in lubrication dispelled many wrong notions. The facility was now ready to engage in “world-class” lubrication.

A new oil analysis lab was chosen to test oil samples. The way oil analysis had been managed previously was poor to say the least. The previous test lab made communication a struggle. The new test lab’s responsiveness was startling. As a result, UOSA became very conscious of lubricant and machine conditions.

With better oil analysis data being promptly reported, the facility was able to identify the “problem child” machines and swing into proactive mode. During the first 12 months with the new oil test lab, many more machines were added to the oil analysis lists. At the end of the first full year, the data was analyzed. Approximately $28,000 had been saved simply by not changing oil when the test results showed normal conditions. In addition to lubrication cost reductions, those “problem child” machines were fixed before they ran to a catastrophic failure and halted operations.

UOSA has now enjoyed the benefits of a robust oil analysis program for more than 10 years. Training has been provided to all technicians involved with lubrication, which has resulted in more buy-in from the workforce. Progress has been slow but steady. Getting buy-in was a struggle.

For approximately nine years, lubrication enhancements were managed in an ad-hoc fashion by the maintenance planners and crafts personnel. In 2014, the mechanical manager suggested formalizing the program with an eye toward consolidating lubricants.

After agreements were reached on making these improvements, the facility evaluated how lubrication was managed. This included a review of how other organizations had successfully approached lubrication improvement. The standout move was hiring a lubrication consultant, who was furnished with a list of lubrication points on the most critical assets. The consultant spent several days onsite, making field visits to machines and reviewing the CMMS lubricant database. These onsite and field visits helped the consultant develop an understanding of how and what should be changed about the program. More than 45 lubricant types were consolidated down to a list of 17. This was called the “consolidation lubricants list.”

Proper oil-dispensing containers were ordered to go with the consolidation oils. What had been designated a lubrication room in the new maintenance building had become a catch-all for spares of all kinds and junk. Lead technician Stephen Myers took on the task to clean out this room, add storage shelving, and order consolidation oils and oil-handling equipment. UOSA even received recognition in Machinery Lubrication’s Lube Room Challenge for this effort.

Custom tags were created to identify and mark each lubrication point. Each tag included the equipment’s unique identifier, the given name of the lubricant and the lubricant code shown in the CMMS. Color-coded dots were also added to the back of each tag as another form of identification.

To help technicians remember the three most important points about the lube program, laminated letter-sized sheets were placed in their PM books, hung in the lube room and left in their vehicles. The points were:

• Use specified consolidation lubricant only when the official light-blue lube tag is installed.
• For topping off, use the original lubricant if the official light-blue tag is not installed.
• When in doubt, contact the maintenance planning office with questions about any lubrication matter.

Additionally, all technicians are regularly reminded to contact the maintenance planning office whenever a lube point is changed to a consolidation lubricant.

Obstacles to Overcome

The resistance to change was the biggest impediment to launching lubrication enhancements. Personnel had performed lubrication in a ritualistic manner for so many years that no one felt a need to change. As lubrication reviews were performed, mistakes were found, like extreme-pressure (EP) oil being used in a gear drive with yellow metal components. Oil analysis revealed this error as high levels of copper and zinc in the oil. Incorrect viscosities, oil with the wrong additives and contaminated oil were also discovered on numerous occasions.

Allowing the maintenance planning office to expand its role in lubrication tasks supported areas into which the field technicians and managers simply did not have time to delve. With a few successes in hand and some avoided catastrophes, word got around and resistance began to fade. The new way was becoming the accepted way.

Refining the Use of Grease

Improving the use of grease was a vital aspect of the lubrication improvements. Many different tubes of grease were in the storeroom. Much of it was ordered and never used or received as spares at the closeout of a project. This selection was reduced to two primary greases and a handful of specialty greases. Colored aluminum washers were purchased to mark grease fittings, and color-coded grease guns were dedicated for these specific greases. This helped reduce bearing failures caused by cross-contamination of incompatible grease types.

Overgreasing of bearings was another important problem to resolve. There was little incentive to take technicians aside to tell them they were overgreasing, show them the right way and follow up with inspections of lubrication work. This would be changed in several ways. One way was by requiring that all electric motors with 75 horsepower or less receive sealed bearings during any rebuilds. This decision was based on motor repair histories. Where a sealed bearing was installed, the grease fitting was removed and replaced with a plug to prevent greasing. This eliminated overgreasing one asset at a time.

The facility has also been working with acoustic lubrication and using ultrasound detectors to signal when to stop pumping grease into a bearing. Another approach has been to add PM tasks with asset-​specific procedures to define the number of strokes from a grease gun to apply at the fitting.

The program is improving steadily, and procedures are being added where a “best guess” existed previously. Grease fittings are still found without lubrication ID washers and protective caps, along with grease spilling out of bearings. On occasion, you might even see grease guns lying in the bed of pickup trucks exposed to the weather.

As frustrating as it is to find some individuals who have not yet fully embraced world-class lubrication, the majority of lubricant handlers were showing interest and making improvements. Perhaps the biggest lesson learned from this experience is how hard it is to change an imbedded culture and how much energy and perseverance are required to sustain change.

UOSA tries to adhere to the Pareto principle, which suggests that 80 percent of your problems come from 20 percent of your equipment. In practice, 20 percent of the total plant equipment provides 80 percent of the benefits and output. The facility endeavors to identify and focus on that 20 percent.

Success Stories

Becoming oriented to world-class lubrication paid off nicely when a biogas-powered reciprocating engine/generator set was installed in 2014. This system uses methane gas produced in biological digesters to fire the engine. In addition to supplying 20 percent of the electrical base load, carbon dioxide is extracted from the exhaust gas and used in the treatment process. Another bonus is capturing the exhaust gas heat to maintain required digester temperatures.

The engine oil requirements for this biogas engine are stringent and allow little compromise. Oil changes for this machine are driven by oil analysis. The staff’s accumulated knowledge and experience with oil analysis has helped keep this valuable asset in peak operating condition. Factory representatives have commended personnel several times for keeping a tight rein on engine maintenance.

One event occurred recently where the base number for this engine’s oil dropped sharply into a caution range well before customary oil life was reached. Additional oil tests were conducted, and similar results were obtained. When the engine manufacturer’s representative was consulted, it was suggested that the content of the biogas be checked. An investigation revealed that the biogas scrubbing elements were exhausted and allowing excessive hydrogen sulfide to pass. This caused the oil additive to deplete and lower the base number. This was another win for oil analysis. It also improved the awareness of maintenance requirements for the scrubbing system.

As interest in lubrication grew, UOSA began to experiment with kidney-loop filtration systems where a cleanup filtering might resolve a marginal lubricant condition. The first targets for this process were the large gear drives on the circular clarifiers. Some of these drives have a capacity of nearly 30 gallons of oil. Hauling a portable filter set to the location made better sense. Technicians connected the filter set and monitored filter back pressure during the filtering period. A follow-up oil analysis sample was taken to confirm an acceptable oil condition and check the process. The overall savings in material and labor have made this an attractive maintenance option. This process also allows the asset to remain in service during filtering with no loss of uptime. In fact, it is desirable to have the drive running to get contaminants into suspension in order to remove them.

Desiccant breathers have been installed on the oil reservoirs of outdoor equipment. This helps keep moisture out of lubricants, and there is always plenty of moisture in a water plant.

Another interesting situation concerned failures in a group of mixer worm drives. These units sit out in the elements exposed to heat, precipitation and cold. The initial failures were caused by using an oil of higher than recommended viscosity. The viscosity was corrected. Then water was detected in these drives during oil analysis. The oil was changed, and desiccant breathers installed.

Factory-supplied oil windows were also replaced with a bubble-type oil port, which allowed visual inspection of the oil level and condition. It was noted that the oil still looked “milky,” so it was drained, and the drives flushed with a new load of oil before a final fill. A week later, when oil analysis was performed again on these drives, water appeared in the sample reports. The percentage of water was less, but it was still there. Prior to this experience, personnel might have let the matter drop after the first oil change and waited for the next oil analysis interval to discover the water. In all likelihood, these drives would have failed before the next oil analysis.

As the lubrication program expands and matures, more stakeholders are buying in. From upper management to junior technicians, it is becoming evident just how much of a foundation good lubrication practices provide. Lubrication is no longer looked upon as a messy job but as the life blood of critical assets.

KPIs Reveal Improvements

In analyzing work orders, the facility began to see more detail in the notes. These details have helped, but they don’t necessarily provide quantifiable results. The graph below shows how emergency work has declined over the years.

While this improvement cannot be directly attributed to better lubrication, it reveals a trend of avoiding emergencies and toward greater equipment reliability. A continuous reduction in the number of oil samples showing a critical condition has also been observed. This represents cost savings and greater uptime. It is believed these improvements are directly linked to better lubrication practices, desiccant breathers, training and pride. Better lubrication practice is a cornerstone of reliable equipment.

Improving Work-order Histories

After moving to the new CMMS, the plant was better able to record and store work-order histories. The “fly in the ointment” was that the organizational culture had not been prone to record details for work-order history. Often the only finalizing comments written on the electronic work order were remarks such as “fixed it” or “overhauled.” There were few comments on the cause of failure and how the corrective work was performed. One impediment to capturing this information was a lack of keyboard skills. Another was the trepidation of technicians to express themselves in writing.

There had been no reward for sharing details, so trade technicians had become somewhat reticent and by turn laconic. Over the past 10 years, a concerted effort has been made to engage and draw out this vital information for work-order histories. The pursuit of world-class lubrication has provided a direct method with immediate and recognizable benefits to show trade technicians that sharing repair history makes their lives easier. It has afforded endless opportunities to compliment technicians and show them the value of their knowledge.

To make work-order histories more useful, the facility has added close-out codes to identify the type of failure. This helps ferret out the bad actors during data analysis. Root cause analysis investigations are actively performed and documented when critical assets are involved. With the lubrication program running and stabilized, attention is now being turned toward precision maintenance.

The single most important aspect in achieving accurate work-order histories is interest. In other words, people in the maintenance planning office must show interest in details. When those details do not present themselves, maintenance planners must go out and hunt them down. It may take some effort to establish a working relationship and get these details, but the rewards are immeasurable. Remember, a single person can start a cultural change, but it takes many people to sustain that change.