By Stacy Heston, CLS, PMP, CMRP, OMA, Lubrication Subject Matter Expert, Allied Reliability Inc.

Lubrication practices are often overlooked as a potential time and money saver for a plant.  However Cargill Charlotte has found that by optimizing their lubrication task intervals, utilizing specific grease volumes, and implementing an oil analysis program, the overall reliability of their manufacturing process, as well as, the healthy status of their lubricated components has increased.
In 2009, Allied Reliability performed a Reliability Centered Lubrication Current State Analysis at the site to determine the state of the lubrication program.  Through the assignment of a score to different lubrication activity and practices, the site’s lubrication program was benchmarked on several parameters including program documentation, management structure and practices, storage and handling, etc.  By assigning a score, the benchmarking activity becomes more objective and less subjective allowing for a definitive path forward.
When Allied Reliability arrived on site, “the site had run amuck with lubricants everywhere, it was all about the flavor of the month…” where lubrication was concerned, and “no structure existed for the scheduling of lubrication tasks,” says Andy Nolan.  As a result of the Current State Analysis, it was determined that a RCL walk down was needed to bring the site up to speed with industry best practices for lubrication.
Shortly after the Current State Analysis, Allied Reliability began the development of a Reliability Centered Lubrication Program at the site.  The program design began with a full walk down of all lubricated components on site.  During the walk down phase, all data pertinent to the development of lubrication specifications, interval calculations, and lubricant quantity calculations is gathered.  This phase sets the stage for the remaining program design as the accuracy and content of this data is the core to a strong program.
During the walk down, opportunities for optimizing intervals are identified as well as opportunities for optimizing the lubricant list.  Optimization does not always mean an increase in intervals or a decrease in the number of lubricants on site, rather it is the assignment of calculated intervals that are specific to the component and takes into account the specific operating conditions the component is exposed to.  Essentially, the same bearing may be exposed to wash down practices and heavy debris requiring an increased interval, such as 30 days to account for these environmental exposures.  However, the same type of bearing operating at the same speed with limited exposure to moisture and no exposure to debris may have an interval of 360 days.  This deviation in intervals means that the bearing with the more aggressive environment and operating conditions receives the more aggressive treatment.
When the Charlotte site began the implementation phase of their RCL program, the lubricated components were in poor health.  Approximately 60% of the oil lubricated assets were considered to be in the red, or in a state that did not meet industry best practices for contamination control, operating temperature, etc.  Within three months, the percentage decreased to approximately 40%.  By the end of 2010, 100% of all oil lubricated assets had achieved a green status.

Components were easily converted from a red state to a green state through the implementation of oil analysis, off line filtration, and monthly inspections.  Oil analysis aids in the identification of in use lubricants that required filtration to clean up solid contaminates, needed refreshing due to changes in additive levels and lubricant properties, or need complete replacement.
Previous to the implementation phase, the site utilized a time based oil change methods, had a multitude of lubricants with no specific requirements for each component, utilized screen breathers, and had no structure for the inclusion of filtration.  Lubricants were stored in drums and in areas that did not provide a clean, temperature controlled atmosphere.  The overall program lacked structure with regards to regrease intervals and amounts, as well as, oil analysis and oil change intervals.
The implementation phase of the RCL Program Design included recommendations for component modification with items such as desiccant breathers, quick connect couplings, level gauges, and sample valves.  These modifications provide multiple benefits for the lubrication program as well as the plant operating structure as a whole.  Level gauges and sample valves allow lube technicians to perform level checks and sample collection tasks with the machine running.  Without these modifications, the machine and possibly the product line would need to be down for the completion of these tasks.  It also saves time from a labor perspective.  A dipstick level indicator involves several steps to determine the level and exposes the lubricant to the possibility of contamination, where as a visual level gauge is nothing more than a quick peek then walk on to the next component.
The Charlotte site followed some very basic steps to manage the program implementation starting with the incorporation of desiccant breathers and other types.  After some experimentation with different types of breathers, there was an eventual shift to the use of trap and hybrid breathers based on the components size and location within the plant.  Of all the modifications, breathers are the least evasive to install, and limits the amount of debris able to enter the sump down to 3µ in size.
The second step included the conversion of mineral based oils to synthetic based oils in the smaller sump components.  Using the current practice of 6 or 12 month oil drains, each sump was converted during the next scheduled oil drain task.  At that time, new intervals of 12 or 18 month were implemented for each sump.  This step applies only to sumps that are too small for oil sampling.
The third step was the implementation of oil sampling practices on sumps within the 4 to 22 gallon range.  This implementation allowed for the extension of oil drains through the monitoring of the lubricant health.  Unlike the second step, these components were not immediately converted to a synthetic oil.  Rather the current lubricant was monitored and cared for until such time the oil analysis results showed a break down in the lubricant properties.  Once the lubricant properties began to degrade, an oil change with conversion to a synthetic occurred.  This maximized the life of the lubricant that was in service before change over without harm to the component.
*During lubricant drains, additional modifications were implemented while the sumps were empty such as the installation of level gauges, quick connects, and sample valves.
Once the oil lubricated components had been addressed, the fourth step was implemented.  The fourth step was the mass implementation of the grease lubrication routes that were developed based on the walk down phase.  These routes were provided in an electronic format which is downloadable to a pda, or other handheld device.  The routes were grouped together based on location within the plant, lubricant required, and interval.  The interval and re-grease volumes are calculated using gathered data to ensure the right amount of lubricant is delivered at the right time.
At the onset of the RCL design, this location had 1 overworked lubrication technician.  Now, they have 1 lubrication technician who is able to complete all required tasks within a timely manner because a solid program structure has been implemented to address all aspects of lubrication.  Task intervals have been optimized to ensure over and under lubrication is not an issue, and oil drain intervals have been extended.  Additionally, lubrication related failures have decreased allowing focus to shift from putting out fires to maintaining the current state.
“We now have a set program that anyone can follow with component state data being collected regularly to ensure appropriate actions are taken to avoid lubricant and component failure.  We have structure and focus.”

By Angie Meinsma, Oil Analysis & Lubrication Technician, Allied Reliability

It is often said that oil is the “lifeblood” of machines and equipment. Taking oil samples from rotating equipment for condition monitoring is like taking blood samples from a human. Analysts look for abnormalities within the fluid. The goal is to find faults, treat the condition, and extend the life expectancy.

When used properly, fluid analysis becomes a valuable diagnostic tool that can reduce maintenance costs, increase productivity, and boost company profits. When used in conjunction with other diagnostic technologies such as vibration analysis and thermography, well-executed fluid analysis strategies can detect a variety of equipment problems before they become failures and give users the valuable time necessary to make decisive, well-informed maintenance decisions. Time has allowed most people and organizations to see the value of integrating the condition monitoring resources for root cause management; they team up to provide control over the root causes of machine failure. Vibration analysis detects abnormal running conditions, such as unbalance, misalignment, and looseness, while oil analysis detects overall lubricant quality and contamination.

The three major reasons for lubricant failure are:
• Contamination – Component life is dependent on the cleanliness of the lubricating fluid. The cleanliness of any lubricant is dependent on oil handling practices, top up procedures, and the quality of both air breather and oil filtration.
• Oil Degradation, specifically oxidation – Oxidation occurs when atmospheric oxygen combines with hydrocarbon molecules and undergoes a chemical change. This chemical change results in the catastrophic and permanent change to a different chemical makeup for the oil molecule. The rate at which the oil molecules react with the oxygen depends on a number of factors, but the most prevalent are temperature and/or additive depletion.
• Additive Depletion – Additives are consumed or chemically depleted while performing their function. After being totally consumed, the additive can no longer provide the special property it performs for the base oil. The lubricant’s performance then suffers, and again the oil must be changed. Each one of these additives has a finite life, and when they reach the end of that life, you can forget about any advantage they helped provide. Some machines rely heavily on this advantage, and when it goes, so does the life expectancy of the machine.

These three factors are why we change oil. No matter what you do, eventually you will have to change it. However, the cleaner, cooler, and drier it is kept, the longer you will be able to go between those changes.

In order to establish appropriate maintenance strategies for your equipment, it is necessary to first understand the failure modes that are inherent in the parts and components that make up your asset base. Once the failure modes are identified, the proper condition monitoring and preventive maintenance tasks can be put in place to identify the warning signs of those failure modes or defects, keeping in mind that the earlier we identify an issue, the better. Unfortunately it is not uncommon for lubrication to be overlooked during the maintenance strategy design session. This is often due to the fact that lubrication is rarely thought of as an integral “part” that comprises your asset. The reality of the situation is that it is in fact a vital part and lubrication failure holds the same consequences as a bearing or coupling failure. Ultimately, the asset fails to perform according to it’s designed function. As with all failure modes, certain condition monitoring technologies are better suited to identify certain failures. This is why lubrication analysis is an integral piece of your maintenance and reliability initiatives.

When condition monitoring technologies are used in conjunction with lubrication analysis, the findings and recommendations are typically far superior. This approach ensures comprehensive coverage consistent with the the likely failure modes of your critical equipment and allows the earliest detection capabilities possible, which foster root cause issue identification. This approach affords ample time to plan, schedule, and perform recommended corrective actions and provides the highest possible return on your maintenance investments.

By: Reggie Fett, Motor Circuit Analyst

Synopsis

Summary of Action

Supporting Data

Conclusion

By: T.J. Garten, IR/MCA Specialist

Bean Conditioner – Horizontal Rotary Vessel

Synopsis

Fault

Summary of Action

Supporting Data

Figure 1: Pre-repair Demodulation Spectrum

Figure 2: Pre-repair Historical Data

Figure 3: Pinion Wear

Figure 4: Broken Welds on Pinion Gear Pillow Block Pedestal

Figure 5: Post-repair Demodulation Data

Conclusion

The corrective action taken during the repair of the failed trunnion bearing resulted in an altered elevation of the rotary vessel. The attempts to adjust for this were inadequate and resulted in a changed mating pattern between the pinion gear and bull gear assemblies. Over time, the increased impacting caused the pinion shaft to deflect, breaking the welds on the pedestals. This deflection also caused an angular misalignment between the pinion shaft and the gearbox output shaft. The level of misalignment may also have been affected by utilizing dial indicators for precision shaft alignment rather than the on-site laser alignment equipment. As the trunnion rollers wear, the clearance between the pinion gear and bull gear’s high spot decreases, resulting in increased shaft deflection. The increased shaft deflection results in transmitted vibration to the feed screw platform and torsional stress on the gearbox output coupling.Future corrections need to take into account all clearances and their effect on correlating components. Monitoring of adjusted components should be within days of adjustments and load changes. Installation of remote accelerometers on the pinion gear shaft pillow blocks would allow for quicker analysis of shaft misalignment, bearing condition, and pinion gear mesh frequencies.

Don’t Let the title fool you, this is a great and very short case study!  Allied Reliability SME Aubrey Green examines a dilemma at a salt evaporation plant in upper NY.  Read it for yourself here:

Radio Frequency Interference on Commtest VBx Series Data Collectors from Improperly Grounded Equipment

Every year Reliabilityweb publishes an eBook on top tips, opinions and viewpoints from industry thought leaders and subject matter experts from around the world.  Stacy Heston, Subject Matter Expert in Lubrication was featured in this 2011 edition with her tips on data entry.  Read it for yourself here:

Things to do and think about 2011- DATA

Allied Reliability’s John Trulli and Bill Kilbey contribute to this ‘Plant Services’ Cover story demystifying the benefits and arguments that swirl around Predictive Maintenance merits, technologies and strategies.   Written by Russ Kratowicz published in April 2011 Plant Services Magazine.  Read it for yourself here:

PdM True Believers: proof of economic benefits can have an astronomical effect

Ricky Smith, Principal Advisor at GPAllied shares the basics on failure modes driven maintenance strategy through this installment of his monthly training topics.  This training is designed for a maintenance manager or reliability manager to train their staff in known best practices.  Read it for yourself here:

Failure Modes Driven Strategy: Monthly Training Topics- Journey to World Class

Daniel DeWald CPIM for GPAllied shares his knowledge and tips on repairing parts before the point of failure as published in ‘uptime’ Magazine’s Feb/Mar 2011 issue.  Read it for yourself here:

Repairable Spares: The Complete Program

SUBMITTED BY: Paul Wright

TITLE: (ASNT) SNT-TC-1A Level II Thermographer
UE Level 1

EQUIPMENT:
69KVA Main Plant Substation 13.8 KV

TECHNOLOGIES APPLIED:
Airborne Ultrasonic (UE)

PROBLEM DESCRIPTION:
Power Outage cause by a main substation tripping on ground fault.

INVESTIGATION:
Upon power restoration, Allied Reliability PdM technicians were brought in to conduct an Infrared and Ultrasonic survey of the Substation. The Technician could only look at the external components thermographically, he then utilized Airborne Ultrasound instrument to listen to the substation and associated distribution equipment.
The Technician found no anomalies with the Infrared scan. The Ultrasonic inspection found an indication of severe tracking in the distribution section of the substation. The smell of ozone was present as well. A visual inspection was conducted during the next planned plant outage. Large areas of severe tracking and related damage were found in the power distribution cabinets.

Tracking damage found in Cabinet. Dirt and other contaminants are also visible.

Insulation materials damaged due to tracking and arcing

Severe pitting and material loss

Main power input connections, sever pitting damage

CONCLUSION:
The cabinets were disassembled and further inspected for damage; affected components were either replaced or cleaned and placed back into service.

Note:

Installation of Infrared Windows to facilitate Infrared Inspections along with periodic visual inspection and cleaning to remove contamination that enables tracking to develop would go a long way in preventing this problem from recurring. Ensuring installed space heaters are utilized to reduce humidity and moisture levels.

Customer Quote / Feedback / Comments:
This is an excellent example of PdM technologies at work and would be an area of opportunity to install Infrared Windows to be able to apply Infrared Technology.  The use of Infrared in conjunction with Ultrasound would greatly enhance the reliability of this equipment