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As Published by Solutions Magazine March/April 2018 issue

by Ana Maria Delgado, CRL and Shon Isenhour, CMRP CAMA CCMP, Founding Partner at Eruditio LLC

During the many root cause analysis (RCA) investigations we facilitate and coach, we notice some themes that continue to manifest themselves in the findings. Often, they are grouped under the heading of precision maintenance or lack thereof. Let’s take a look at some of them and determine if they are also killing your reliability.

The six killers are grouped into three areas: Lubrication, Misalignment and Undiagnosed Wear.

Click here to read the full article.

Plant Engineering, celebrating its 30th anniversary of the Product of the Year award program, announced the results for the 2017 entrants. SDT’s innovative LUBExpert, an ultrasound solution designed to help grease bearings right, was awarded the GOLD medal! The award is remarkable considering the excellent company of peers in the running for Silver and Bronze.
Alex Nino of LUDECA, was on hand at the award ceremony, and looked marvelous! LUDECA is the exclusive distribution partner for SDT Ultrasound Solutions in the USA and were instrumental in architecting this recognition. Chosen from numerous submissions from around the world, Plant Engineering subscribers reviewed and voted on the finalists. LUBExpert received the most votes for this 30th anniversary Grand Award. Congratulations to LUDECA, SDT, and LUBExpert for the GOLD.
Poor greasing practices is a leading cause of bearing failure. LUBExpert is an ultrasound solution designed to precisely guide lube-techs during the lubrication replenishment process. It helps avoid over and under lubrication, while instructing the technician on which grease types, grease guns, grease quantities, and replenishment intervals to use. LUBExpert’s intelligence lends confidence to the task of grease replenishment and is a true innovation for ultrasound technology.

Winning GOLD validates our decision to work with industry leaders such as SDT,” states Ana Maria Delgado, Marketing Manager at LUDECA. “The LUBExpert compliments our full line of predictive and proactive solutions. Its clever innovation supports the leadership position of all our solutions.”

About LUDECA
LUDECA is the premier provider of reliability solutions to USA industry. Their years of experience and wealth of knowledge make it possible to offer the very best service and support to their customers. Their commitment here strengthens their reputation as the very best in our fields. SDT is delighted to be aligned with LUDECA. Our companies share the same principles, philosophies, and values.
About SDT
SDT provides ultrasound solutions that help our customers gain a better understanding about the health of their factory. We help them anticipate failures, control energy costs, and improve product quality while contributing to the overall reliability of their assets.

Bearings are a critical part of the design and function of most mechanical equipment. The majority of bearings never reach their intended design life due to improper selection, storage and installation. Unfortunately, this results in compromised equipment operation, lost capacity and increased costs. Do not condemn your equipment to death through improper bearing storage practices. Below are a few storage tips to help your facility ensure bearing reliability:

• Store bearings in a clean, dry and low humidity environment (moisture from environment, gloves, etc can result in corrosion and/or etched sections creating fatigue on the bearing.) Avoid storage near direct sunlight, air conditioners or vents.
• Eliminate shock/vibration.
• Do not store bearings on the floor (will introduce contamination, moisture and vibration/shock.)
• Store bearings on a pallet or shelf in an area not subjected to high humidity or either sudden or severe environmental changes.
• Store bearings flat and do not stack them (lubrication and anti-corrosion material may squeeze out.)
• Do not remove bearings from carton/crate or protective wrappings until just prior to installation in the machine (be careful of bearings in wooden crates as these could attract moisture – perhaps best to remove them from those cases.)
• Do not clean bearings with cotton or similar materials that can leave dust and/or contamination behind (use lint free materials.)
• Do not handle bearings with dirty, oily or moist hands.
• Do not nick or scratch bearing surfaces.
• Always lay bearings on clean, dry paper when handling.
• Keep bearings away from sources of magnetism.
• Do not remove any lubrication from a new bearing.
• Lubricant in stored bearings will deteriorate overtime. The bearing manufacturer should specify shelf-life limits. These dates should be noted on the packaging and monitored to help ensure bearings are fit for use when needed.
• The following visual inspections of bearing integrity should be completed periodically and just prior to use:
  • Examine packaging for indications that the bearing could have been damaged during shipment or storage. The bearing should be discarded or returned to the supplier if signs of damage are found.
  • Examine the grease or oil for evidence of hardening, caking, discoloration, separation, etc. Re-lubrication for continued storage or replacement maybe required.

Miss Part 1 of 2? Here it is: Has your Equipment Been Condemned to Death? Proper Lubrication

Lubricant received from suppliers has been shown statistically to contain high levels of contamination. Improper facility storage of that lubricant allows additional particle and moisture ingress. Improper dispensing of this lubricant introduces added contamination as well.  The accumulated water/moisture contamination causes the lubrication film to weaken and allows the rotating surfaces to move closer to each other during operation. The particle contamination then more easily damages gears, bearings, etc., and greatly shortens the life of your equipment. Contaminated lubricant can shorten equipment life by 75% or more.
To prevent this, ensure that lubricants are filtered and clean before entering your equipment. Store lubricants in a clean, dry and cool (temperature controlled) environment. Don’t leave lubrication containers open and exposed to the environment. Do not allow the containers to become a catch-all for dirt and moisture.
Proper lubrication controls do not have to be expensive. In fact, some of the greatest reliability improvements can be implemented quite inexpensively. Do not introduce equipment defects and condemn your equipment to death through improper lubrication practices and other poor maintenance practices.

Bearings produce less friction when they are properly lubricated. But how do we know?

• How can you be confident that friction forces are where they should be?
• How can you confidently apply just the right amount of grease to return friction levels to normal?
• How can you distinguish between a bearing that needs grease and a bearing that is failing?

How does Ultrasound help?

Using an ultrasound measurement tool with digital decibel metering is a proven method for:

• Establishing a historical baseline for friction levels
• Monitoring changes in friction levels at regular intervals
• Triggering alarms when friction levels elevate
• Evaluating data to differentiate failure from friction

Our ultrasound solutions are designed for budget-minded inspectors. However, attention to detail, robustness, and quality have not been sacrificed at the expense of low prices. Equipped with needle and threaded contact sensors, acoustic lube adapter, and multi-surface magnet, our SDT systems answer the basic needs of lubricators. The non-contact temperature sensor can be used for additional control of bearing condition prior to and after lubrication.

Download our Ultrasound Lubrication Technician Handbook.

To facilitate the initial learning curve, a labeling system was implemented to help technicians collecting data identify bearings that were part of the initial survey. These descriptors were laminated to prolong their life in the unfriendly environment of a typical cement plant. Standard locations for data collection needed to be understood since labels would become difficult or impossible to read over time.
On the job training included understanding that readings collected on the drive motor bearings needed to be collected from the grease fitting on the non-drive end and from the upper portion of the end bell housing on the drive end. On driven equipment bearings, where direct access was possible, the ultrasound readings were to be taken in the horizontal plane directly from the bearing housing. (Note: with ultrasound it is not necessary to record data from multiple planes on the same bearing). Technicians were trained to take ultrasound readings as close to the bearing as physically possible while respecting personal safety.
This simple label proved important to the integrity of the pilot project to prevent greasing from well-intentioned lubricators.

Like any job there is a right way and a wrong way to do things. Simply listening to a bearing with an ultrasound device that gives no quantitative feedback is a recipe for disaster. The audible feedback is too subjective to draw any comparative conclusions. No two people hear the same and there is no way to remember what the bearing sounded like a month ago.
The third mistake is depending solely on subjective ultrasound data when precise quantifiable data is available. Always use an ultrasound instrument with digital decibel metering. Better still, use a device that provides multiple condition indicators. Max and Peak RMS decibel measurements indicate alarm levels and greasing intervals while Ultrasonic Crest Factor provides insight about the bearing condition in relation to its lubricant. Crest factors help us differentiate between bearings that need grease and bearings that need to be replaced.
Download the Ultrasound Lubrication Technician Handbook

The second mistake we should all avoid is adding too much, or not enough grease. Too much grease builds up pressure pushing the rolling elements through the fluid film and against the outer race. Increased friction and temperature dramatically shorten the bearing’s life. Not enough grease will have the same life-shortening effect.
How do we know when just the right amount of grease has been added? Ultrasound of course. Listen to the bearing and measure the drop in friction as the grease fills the bearing cavity. As the decibel level approaches normal baselines and stabilizes carefully slow the application of lubricant. Should the decibel level begin to increase slightly, STOP! The job is done.
Download the Ultrasound Lubrication Technician Handbook

Lubricating a bearing once per week or once a month may seem like a sensible thing to do. After all, performing scheduled maintenance at regular periods is an age old concept ingrained in each of us early on. Even OEMs still advise best practices based on time intervals to ensure maximum asset lifespan.
The problem with any blanket solution is that they ignore the effects of variables.
Two motors may be the same out of the box but end up in entirely different situations. While one lands in a hot and humid climate, another could be installed in a cold and arid climate. One may be used in a high speed low load application while another at low speeds but with frequent starts and stops.
It is irrational to expect the maintenance needs of one to be the same for another when the conditions they operate in are so different.
Bearings need grease for one reason only; to reduce friction. As long as the lubricant is performing that service well, there should be no need to change it. Yet we frequently do, with catastrophic results.
Re-lubricating a bearing just because your calendar told you “time’s up!” is the first mistake. Monitor ultrasound friction and know when it’s the right time to grease.
Download the Ultrasound Lubrication Technician Handbook

It can be argued that lubricants are the lifeblood of equipment. It is extremely difficult to assure equipment reliability when lubrication integrity is not maintained. The key is to keep the lubrication system clean, cool and dry.
According to the Arrhenius Rate Rule, every 18-degree (F) increase in oil temperature in operation reduces oil life by half. Excessive lubrication temperatures can lead to additive depletion, oxidation, varnishing, hazards, corrosion, increased frequency of oil changes and more. All of this leads to reduced equipment reliability and increased costs.
Reduced operating temperature is one of the many benefits associated with proper machinery alignment.  This in turn will help you reduce the operational temperature of the lubricants (lifeblood) within your equipment.  Best practice equipment reliability includes proper equipment alignment. Your best practice lubrication efforts should include making sure your equipment is operated within proper alignment tolerances. Doing so will help you maintain the “cool” required to ensure that the lifeblood of your equipment is protected.

Today’s more evolved ultrasound data collectors present results that take reliability practitioners beyond the single decibel. Using only an overall dB value may indicate something inside the machine has changed since last readings were taken. But it provides no additional insight to determine what type of defect may be present.
Moreover, a single dB only provides a useful trend if the inspector has control of the acquisition time during data collection. Acquisition time needs to be adjusted in concert with the speed of the machine. More time for low speed applications and less for high. The aim should be to capture a minimum of 2-3 full shaft rotations.
The SDT270 takes inspectors beyond the single decibel by presenting ultrasound data in terms of machine condition. We call them Condition Indicators and there are four (RMS, Max RMS, Peak, and Crest Factor (CF)) and are abbreviated as 4CI. Ultrasound identifies defects in machines when those defects produce one or more of the following phenomena: FRICTION, IMPACTING, or TURBULENCE (FIT).
Some examples:

• A bearing that requires lubrication will present higher levels of friction. Therefore, an RMS danger alarm will be triggered at 8 dB and an RMS/CF alarm when severity increases.
• A bent shaft produces higher levels of friction and therefore present danger and alert warnings with the RMS condition indicator.
• Electrical defects such as arcing, tracking, and corona are first alarmed with the RMS condition indicator and severely alarmed with Max RMS and CF.
• A faulty steam trap is detected with an elevation in Temperature and Max RMS.

Traditional ultrasound is useful for trending decibel levels that alert us when machine condition changes. Evolved ultrasound goes beyond the single decibel to recruit Condition Indicators that help inspectors determine the type of defect that is creating the alarm. SDT’s Four Condition Indicators demonstrate how ultrasound must be used for both defect alarm and identification.

Reposted from RELIABILITYWEB®

1. Assemble a team and identify applications for a program
2. Justify needs by recognizing key areas where improvement can be benchmarked
3. Set written goals for the program
4. Establish how ROI will be measured
5. Purchase quality ultrasonic inspection equipment
6. Invest in certification training at both management and user levels
7. Choose a leader to technically carry the program forward
8. Establish a system to reward the successes
9. Frequently review the progress as part of regular meetings
10. Ensure everyone involved is 100% mentally invested in the program’s success

Tip from Hear More: A Guide to Using Ultrasound for Leak Detection and Condition Monitoring by Thomas J. Murphy and Allan R. Rienstra.
To learn more about airborne ultrasound,  download a chapter preview of Hear More.

Have you ever been asked “How much longer will it run” or “Can we make our production schedule” or other ‘crystal ball’ type questions? These types of questions can be very difficult or virtually impossible to answer. They often place a reliability professional in a difficult position.
Some future indicators are (or should be) available to your organization that will help you answer the above questions when asked. Four of those indicators are:

1. Preventive Maintenance (PM) Completion Rate
   Low PM completion rates directly correlate to increased future equipment maintenance work. High PM completion rates mean that needed equipment maintenance is being completed and future maintenance issues will be avoided.
2. Ready to Work Backlog
   This is an indicator of preparedness and efficiency to complete maintenance work.
3. Outage Schedule Compliance
   This is a very important metric to track and is an indicator of future maintenance work. A lack of adherence to outage schedules creates deferred equipment maintenance. This results in increased risks and likelihood that equipment performance will decrease at a future time,  leading to lower capacity, increased downtime, and greater expenses.
4. Equipment Asset Health Reporting
   Proper utilization of condition monitoring technologies like vibration analysis, IR thermography, lubrication analysis, ultrasound and others are a proactive strategy to ensure that hidden failures become known and corrected before they result in equipment downtime or other unwanted consequences. Tracking these indicators together can provide insights into future asset health. A lot of “red” assets from these technologies will result in future unwanted equipment maintenance and unwanted downtime if corrective action not taken. Additionally, this can be used to help prioritize equipment maintenance efforts if a good critical equipment ranking system is in place.

All machines and their components will exhibit wear at some point. This can lead to loss of function and require corrective action.
Wear particles are one of the most common sources of equipment reliability problems. They indicate that the oil is unfit and unreliable for operation in the equipment and will lead to damage in the equipment. These particles can give an insight on the type of equipment problems as well. The characteristics of wear are specific from machine to machine.
A facility in Texas lost key personnel in their condition monitoring program and experienced a gearbox failure. The plant was in need of a true online monitoring system for small and large particle quantities. They purchased the WEARSCANNER oil particle distribution solution as a result. The WEARSCANNER solution not only counts and classifies, but also has the ability to count low and high particle flow speeds which is of value to the customer. The customer was able to adjust the different size classes in accordance to ISO 16232 and have the data fed directly into their control system.

Guest post by Dave Tiffany, Reliability Specialist for Pioneer Engineering
If you have a gearbox with a manufacturer’s nameplate instructing you to use the American Gear Manufacturer’s Association (AGMA) #4 viscosity oil at a given operating temperature, or if it specified a 750 SSU viscosity oil, would you know exactly what viscosity oil you need? If your grease application specified a base oil viscosity of 220 cSt for a given operating temperature would you know which of your greases might fit that specification, if any?
Does it really matter? Oil is oil, grease is grease, and more is better, right?
WRONG!
The importance of proper oil viscosity in your large array of equipment and the varying lubrication regimes they present is one of the most important maintenance practices one can focus on in their facilities. Viscosity is the most important physical property of a lubricant, and viscosity is the most important specification for a lubricant. Along with this, viscosity is the easiest thing to mess up!
A simple definition of viscosity is the thickness of an oil. While this is the most common understanding of viscosity, a more technical definition of viscosity is a measurement of the oil’s internal resistance or its resistance to flow by gravity. Viscosity is what carries the load, separating surfaces in relative motion from touching, thus reducing friction and wear, extending equipment life.
Viscosity should always be measured at a given temperature. Normally viscosity is inversely proportional to temperature, meaning as the temperature of an oil increases, its viscosity generally will decrease.
Stating an oil’s viscosity is found in many different formats depending on the application. The International Standards Organization (ISO) is the universally accepted method for stating oil viscosity (ISO VG) through-out industry (ISO 3448). This ranges from an ISO VG 2 to an ISO VG 3200. ISO VG is stated at 40°C.
AGMA specify grades an oil’s viscosity for industrial gear applications, also at 40°C. The AGMA uses a #1 through #8A designation.
SUS – or – SSU is not in use much anymore, but you may still find it referenced on an older gearbox nameplate or an OEM (original equipment manufacturer) manual. This stands for Saybolt Universal Seconds – or – Saybolt Seconds Universal, you’ll see it stated either way.
Society of Automotive Engineers (SAE) Crankcase and SAE Gear classifications are different yet. 0W, 5W, 10W, etc., and straight weights 30, 40, and 50 are designations for crankcase oils, while 70W to 85W and 80 to 250 are designations for automotive gear oils.
If all of this is making sense, I commend you. You are likely on top of your game and know exactly which oils and viscosities belongs in each application throughout your facility. But if this sounds like a foreign language that you do not understand, it’s okay, as long as you now realize that your equipment may be in jeopardy of shorter life cycles and there is potential for cost saving improvements that will greatly enhance your equipment’s reliability.
 

Engineering advancements have resulted in many different types and grades of lubricants being available for equipment maintenance. Unfortunately,  the risk of improper selection and mixing of lubricants has increased as well. Mixing different types of lubricants (grease and oil,  etc.) within a machine is one of the most common equipment reliability problems. Doing so can result in unanticipated chemical reactions and equipment failures.
Proper labeling is a method to help ensure that the correct type of grease or lubricant is being injected into your equipment. Color coded labels with proper lubricant identification markings should be placed on the Zerk fitting or near any lubrication entry point on a machine. Grease guns and lubricant containers should have the same color identification and markings as well. This simple process can assist in eliminating lubricant contamination and thereby prevent one of the most common reliability problems today.

Guest post by Brad Loucks,  Mechanical Engineer at Pioneer Engineering
When discussing machine lubrication techniques and associated maintenance tasks with industry personnel, I often hear the same story; “Once a month, we fill it up until it’s full.”  This story can unfold further to reveal that every piece of machinery under such a program receives the same type of lubricant with no considerations made to temperature change, operating conditions, load requirements, and duty cycle.  Technology has come a long way over the past several decades in every corner of the modern world and machine lubrication and oil analysis is no exception to this evolution.  It has been discovered that choosing the right lubricant for the application significantly prolongs machine life and maintains the overall health of rotating equipment in use today.
To further illustrate this point, just consider how much thought is given to the type of oil used in your car.  You won’t find a can of automobile oil in the store that is simply labeled, “Oil”.  Instead, you will find several types of oil that are specifically designed to resist large viscosity changes with changing temperature.  The ability to resist significant viscosity change is depicted using the nomenclature, “10W-30”, or “5W-40”, etc.  A common misconception is that the “W” stands for weight.  Instead, the “W” stands for “winter”, and the number that precedes it represents the oil’s ability to resist thickening when the temperature is 0° Fahrenheit.  Similarly, the second number represents the oil’s ability to resist thinning in an environment where the temperature is 100° Fahrenheit.
As you can see, operating environment and temperature play a big role in choosing the right lubrication to extend the life of an automobile engine.  In an industrial setting, machine lubrication plays an even larger role with proportional consequences and benefits to the amount of thought and detail given to choosing the right lubrication.
Recent advancements in technology now provide us with addition tools to collect and analyze oil samples in rotating machinery.  In doing so, maintenance technicians are able to better understand the present health of their equipment as well as make determinations for further maintenance tasks to be performed.  The difference between this story and the “Once a month, we fill it up until it’s full” story, is that we now have the ability to schedule maintenance tasks based on condition, instead of relying solely on a time trigger.  A proper machine lubrication program enables us to recognize the root causes of machinery failure due to improper lubrication.  A successful lubrication program also incorporates methods in identifying lubricant contamination and implements the best practices in lubricant storage, handling, and dispensing.  By introducing these condition-based methods of scheduling maintenance tasks, machinery health is better managed, saving time and money.

Ingression can be defined as going in or entering,  a right or permission to enter, or a means or place of entering. It is important to understand, recognize, detect and reduce the effects of particle ingression. Doing so will have a very positive effect on your maintenance and reliability efforts.
Dirt is often the root cause leading to bearing damage and reduced equipment reliability. If not monitored correctly, ingression can lead to unexpected failures resulting in high maintenance and inventory costs.
When measured in the Moh’s Hardness scale, dirt is typically more abrasive than the bearing material. This leads to pitting and other damage to the bearing that reduces the life of the equipment. It’s really quite simple: under great load something has to give and it’s usually the bearings, gears, pump impellers, etc. Our goal should be to remove contaminants from the lubricant to our target cleanliness before placing it in our equipment. Doing so will increase our equipment reliability.

Guest post by Kasey McClain,  Mechanical Engineer at Pioneer Engineering
Everyone knows that lubrication is crucial to the life of a bearing. Two common types of bearing lubrication are grease and oil.  I commonly see oil bath lubrication and oil mist along with grease lubrication.  One of the biggest problems that I have encountered with greased bearings is over greasing.  When installing a new bearing assembly, it is important to note whether the bearings are pre-greased by the manufacturer.  Over greasing will not allow the heat to dissipate from the bearing which will cause the bearing to expand and cause a tolerance stack up which may then show bearing defects.  This may also cause an existing defect to progress, decreasing the life of the bearing.  With an oil bath lubrication system, too much oil can be just as detrimental as too little oil.  With too little oil, the slinger ring, or whichever component carries the oil, will not be submerged in the oil and will not be able to lubricate the necessary components.  With too much oil, some of the components may not get the lubrication necessary.  Oil mist systems have been shown to eliminate the issue of too much or too little oil.  However, running the mist system low on oil will cause the components to not be lubricated.  Also, the oil misters can become clogged which would lead to a lack of necessary lubrication.  This is why regular lubrication monitoring is necessary to keep equipment running smoothly for as long as possible. Attention to detail is essential in all aspects of machinery maintenance.

The Finger as a Sensor and Other Things That Are Of Utmost Importance!
Toyota did a study to find out why some equipment failed prematurely. They found that something like 80% of premature equipment failures could all be traced to three rather simple causes; causes that could have been prevented or remediated before they led to equipment breakdown. What were the three culprits?
a. Looseness
b. Improper Lubrication
c. Contamination
All three of these can be addressed by the vibration analyst during collection and analysis.
Looseness can be detected with a vibration analyzer. When you see looseness,  use your finger as a sensor and run it around the interfaces of the bearing pedestals, housings, and foundations. It is surprising how sensitive one can be to the phase difference of shaking parts that have become loose. See that it is remedied before it causes catastrophic failure.
Inadequate lubrication can be detected by Shock Pulse. If you are taking high frequency acceleration readings it will cause a raised noise floor. This one is best avoided altogether by a well-planned and supported lubrication program. Often, by the time poor lubrication is detected, a considerable amount of damage has already been done. An electric motor’s winding insulation breakdown rate is doubled for every 18° F rise over 165° F. This is why motor cooling fins are actually for cooling and not for holding dust, grime, or whatever. Contamination is an important condition to monitor via a manual input point for each machine area. Add it to your route. Report equipment covered in whatever foreign matter your plant has lots of so it can be properly cleaned before damage is created.
Focusing attention on the three areas above will definitely create value for your company.