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Understanding the Key Components of an Effective Lubrication Program

Lubrication is often overlooked in organizations.  Why it is overlooked, I am unsure.  Maybe it is because it is considered to be a basic job, given to the apprentice, or it is just too simple not to do it correctly.

However, with a focus on lubrication, many failure mechanisms can be reduced and the equipment life prolonged.  But implementing an effective and world-class lubrication program is not simple.  It requires a dedicated focus to implement and sustain.  Below is my list of what I look for when evaluating a lubrication program.

1. Properly Trained Specialists – Any program worth implementing requires having staff trained properly.  Depending on where the focus is, there are many different options for training and certification in machinery lubrication.  The International Council for Machinery Lubrication (ICML) offers numerous certifications and levels, whether you are a technician, analyst, or lubrication engineer.  Ideally, all technicians that perform lubrication activities will be trained and certified to MLT I, and those managing the program will be a minimum MLT II.  Selecting the right training for your staff requires an understanding of where the program will be.  Lastly, be sure to select reputable trainers in the field of lubrication.
2. Proper Storage of Lubrication – A great tell-tale sign of the state of the lubrication program, is to walk through and look at the oil room.  How clean is the room?  Are there open containers?  Are the new lubricants clearly labeled, and in sealed containers?  Is old oil mixed in with new oils?   Having an organized and clean storage for lubricants is vital.  It is the first step to preventing cross-contamination and contamination of the oil.
3. Identified Lube Points – Identified lube points is not just labeling each lube point in the field with a colored cap or tag.  It may make more sense to have all of the lube points indicated on the PM procedure.   The goal here is to make sure all lube points are identified, so not one is missed during the course of a lube route.  The lube points also need to have the type and quantity of lubricant required (once again, this may be in the procedure or in the field).
4. Avoiding Cross-Contamination – By properly labeling the lube points in the field, the chance of cross-contaminating the lubricant is reduced, but it is not eliminated.  There should be dedicated containers for each type of lubricant (sealed transfer containers, grease guns, etc.).  This will ensure there is no potential for cross-contaminating oils with others (as many additives are not compatible with each other).
5. Preventing Contamination – Preventing contamination is critical to keeping not only the lubricant clean but the machinery as well.  Preventing contamination starts with the oil room, and having desiccant breathers and filters on any drums of oil.   In the field, there needs to be desiccant breathers and filters as well.  Why?  As the gearbox heats up and cools, the air inside expands and contracts, which pulls in external air, moisture, and anything else in the air.   When it comes to greasing, it means appropriately cleaning the grease zerts and grease guns before applying grease to the equipment.
6. Ensuring Clean Lubricants – Do you think that the oil coming in from the vendor is clean?  It may be clean, but is it clean enough for your application?  Before transferring oil from the storage container to the asset, it should be filtered to meet the needs of the asset.  Use the ISO Cleanliness guidelines to help select the right cleanliness for your application.
7. Oil Analysis in Place – Oil analysis should be used in two ways.  The first is to understand the condition of the lubricant and make an informed decision on whether to change the lubricant or not.  The oil replacement should be driven by the condition of the oil, not strictly by time.  The second way it is used is to understand what is going on inside the asset by understanding wear particles, etc.   The success of an Oil Analysis depends heavily on the collection and handling of the sample.  Therefore, I often look for oil sample collection procedures.
8. Acoustic Lubrication – This takes the time-based re-lubrication task and expands it to ensure that the equipment is neither over lubricated or under lubricated.  It also provides insights into the condition of the equipment, complimenting vibration and oil analysis.
   Download LUDECA’s 5-Step Acoustic Lubrication Procedure – an effective lubrication procedure to grease bearings right
   
9. Minimal Lubricants – contamination and improves the purchasing power of the organization.

Effective lubrication takes many of the practices mentioned above and provides a governance framework to support and ensure it is executed as designed. With an effective lubrication program, the organization should see an increase in uptime, a reduction in lubrication consumption, and a reduction in the number of lubricants on site.  These changes enable the organization to operate more efficiently.

Next Steps

To begin the journey to improve your lubrication program, you do not need a full assessment and massive project.  Take one of the items above, learn more about it and start a pilot.  Make sure to build a business case with your pilot to capture the benefits and use that as a basis to build the business case for the larger project.

Thank you James Kovacevic with Eruditio LLC for sharing this informative article with us!

Sources of Equipment Damage: Funnels

Maintaining proper oil levels in our equipment is a critical maintenance function to keep our assets running and producing product. Adding (or topping off) oil in our assets requires a means to transfer the lubricant from a container to the machine. The means used to accomplish this task are much more critical than may be commonly understood.

What is the Common Lubrication Practice at Your Facility?

Does your facility use some type of funnel as a transfer mechanism? While funnels can make this task easier, they are not recommended because of their potential to introduce contaminants into the lubricant.

Funnels are usually stored in dirty environments in the plant and are therefore constantly exposed to dirt and dust. Even wiping off the funnel before use exposes the funnel to even more contaminants that enter into our equipment and cause damage.

As a lubricant flows through the funnel, it carries along all the dirt particles on the funnel straight into the machine. Not only large particles, but very small particles that can’t be seen with the human eye enter into the equipment and cause the most damage.

Another risk of funnels is the potential for cross-contamination between two incompatible lubricants. Many oils on the market, when mixed with another lubricant, can easily cause severe machine damage. Most funnels are not color-coded or labeled in a way that would designate them to be used only for a particular lubricant. Therefore, a number of different oils may flow through the same funnel, potentially contaminating the lubricant inside the machine and causing significant damage.

Best Lubrication Practice

A sealable and reusable (S&R) container is a “best practice” alternative to a funnel. These containers typically have a spout or pump-style lid, making it easy to transfer lubricants from the lube room to a machine in the plant. However, the main benefit of these containers is that they lower the chance of particle ingression and cross-contamination into your equipment.  This prevents equipment failures, unwanted downtime and improves plant capacity.

You can learn more about Lubrication Best Practices from Paul Llewellyn at our Rethink Maintenance Training Roadshows

Best practice lubrication requires filtering out particles to the proper ISO code for the type of machine. One way to keep your equipment lubricant clean is by installing good quality desiccant breathers. Desiccant breathers replace the standard dust cap or OEM breather cap on equipment and provide much better particulate and moisture filtration. Not all desiccant breathers offer the same amount of protection. I recently visited a facility that was using desiccant breathers on their critical equipment. Unfortunately, these breathers only provided particulate filtration down to 10 microns, allowing harmful particulate ingression directly into their critical equipment and potentially creating unwanted equipment damage and downtime. This is why desiccant breathers with specific features will protect your critical equipment from damage and unnecessary repairs: A two-stage particulate filter system that incorporates a minimum of a 3 micron particulate filter and a “sponge” to capture oil mist that is contaminated is one such. A stand pipe within the breather that protects the reservoir from desiccant in the event of something breaking the breather while in application is also a good idea.

Check out Lubrication Engineers’ full line of desiccant breathers for contamination exclusion in industrial applications or learn more about Lubrication Best Practices from Paul Llewellyn at our Rethink Maintenance Training Roadshows

Guest post by Paul Llewellyn – LUBRICATION ENGINEERS

If manually greasing a bearing typically means that the bearing will end up being over-greased because more often than not the person doing the greasing pumps new grease in until new grease comes out the other side of the bearing, and over-greasing is as bad as under-greasing, then why don’t more facilities use fully automatic or single point lubricators which can prevent this problem?  Let’s take a look at some of the positives associated with automatic lubrication and SPLs.

Advantages of a Single Point Lubricator (SPL):

• Reduce work place hazards. Keep employees safe in situations where bearings are cage enclosed and a lock-out/tag-out is required to simply grease a bearing. Instead, remote mount outside of cage. Machine gets greased while in operation. Keep exhaust fans properly lubricated without the risk to personnel (annual greasing instead of monthly). Hard to access bearings can now be properly greased with a remotely mounted SPL that can be easily monitored and changed out (conveyor systems, for example).
• Precise lubricant delivery. Automatic greasing puts the right amount of grease, in the right place, at the right time, using the correct grease. This means no lube mixing and a reduction in the amount of grease purchased.
• Improved machine reliability/availability. 50% of all bearing failures are due to lubrication issues. Properly lubricated bearings last longer and increase uptime and throughput. A reliable asset is a safer asset.
• Man-hour availability. Automatic greasing and SPLs free up personnel so they can do other more productive tasks related to maintenance and reliability-centered maintenance.
• Automatic lubricators and SPLs work 24/7/365. Once installed and set correctly, these systems are never late, never sick, don’t take vacation and deliver consistent results time after time.
• Environmental benefits: Automatic systems and SPLs keep the correct amount of grease in the bearing so high moisture areas, dusty and dirty applications, higher temperature assets and other environmental conditions have less of a negative impact.

If you are trying to improve the reliability program at your facility, consider automatic lubrication and Single Point Lubricators as a simple place to start.  You will see immediate benefits with improved bearing life, parts and labor reductions, less unscheduled downtime and increased production and profits.

Learn more about Lubrication Best Practices from Paul Llewellyn at our Rethink Maintenance Training Roadshows

While we’ve been using calendars and calculators to determine grease replenishment requirements in bearings for a long time, this science is wrong. Most bearings never reach their L₁₀ engineered life, and poor lubrication practices are attributed as the primary failure cause.

Bearings fail when they are over-greased. We lubricate them too often, and we use too much grease.

Change Your Thinking.
We lubricate bearings to manage friction, but over time, grease gets old and needs replenishment. The first sign is when friction levels increase. Ultrasound performs well at sensing and measuring changing in friction levels. It’s the perfect technology to guide lube technicians during the lubrication-replenishment task.

Lubrication Solution
We want to grease bearings correctly. That means using the right grease, at the right location, following the right procedures and intervals, injecting the right amount, and receiving the right feedback when the task is done. New technologies from SDT are engineered to do just that.

The days of relying on calendars and calculators are over. Use our 5-Step Acoustic Lubrication Procedure  and start greasing bearings the right way!

Download our Ultrasound Lube Technician Handbook to learn more!

Guest post by Paul Llewellyn – LUBRICATION ENGINEERS

Is new oil clean oil? That is a question that can be debated, and has been, for many, many years.  If the new drum that was delivered to my dock, destined for my hydraulic equipment, has never been opened, how can the oil inside it be “dirty”?

To answer that question, perhaps we need to look at a typical journey for a drum of “new” oil.  Most commercial oils leave the finished lubricant manufacturing location in a bulk tanker truck destined for several local oil jobber or distributor locations.  First question: How clean was the tanker truck’s tank when the oil was pumped into it? What method was used to fill the tanker? Was a hose used that had been lying around the filling area floor?  How many stops were made before the tanker arrived at your supplier’s location?

Once arrived at the jobber location, the oil is off-loaded into bulk storage silos on site.  Again, what was the method used to off-load the bulk oil?  Is there a dedicated pump and hose for each different type of oil being off-loaded and stored, or do they flush the same pump and hose and use just one? Where and how were the pump and hose stored?

Once on site, the oil then has to be transferred into the container that you ordered.  Let’s say that’s a 55-gallon drum.  Has that drum been used before and is simply refurbished for reuse? How was it cleaned? What oil was in it before? Is it rusty inside? Does it contain moisture? Dirt?

And what if you ordered a small tanker delivery of say 300 gallons for the 500-gallon stationary tank at your facility? Are you the first stop of the day for the delivery driver or has he been off road on dirt and gravel to five different construction sites before showing up at your facility? Was he/she trained in contamination control best practices?  Most likely, they have no training in that area.

So, it is fairly easy to see how new oil can become dirty and most likely is too dirty for use in a hydraulic system.  It is best practice to take an oil sample of the new oil upon arrival.  This will tell you whether the oil in the container is actually the oil you ordered and what cleanliness level the oil meets.  Then, best practices dictate that you filter that oil before you put it into your expensive equipment.  And use dedicated pumping equipment for that fill. Don’t pay for the cost of reliability with the consequences of unreliability!

Learn more about Lubrication Best Practices from Paul Llewellyn at our Rethink Maintenance Training Roadshows

Download Oil & Grease Storage Best Practices

1. Prevent metal-to-metal contact (which creates wear particles) by using condition-based lubrication through ultrasound. Ensure the proper oil viscosity and additive package is selected and that the bearing load does not exceed its design capacity through proper installation, alignment, balancing and operation.
2. Use desiccant breathers.
3. Adopt an aggressive fluid management program that establishes acceptable ISO cleanliness targets for new oil by machine type. Take care to use methods of adding and sampling oil that minimize contamination ingress. These include quick connect couplers and point-of-use filtration. Install an oil recirculation system to remove particles as soon as they are created and introduced.

Guest post by Paul Llewellyn – LUBRICATION ENGINEERS

As with so many things, such as dogs, all greases are not the same. There are greases that are made simply to meet the slimmest of specifications and then there are greases designed to far exceed basic performance specifications.

Greases are primarily made up of oil (70%-95% base oil) of a certain viscosity that is held (like water with a sponge) with some type of thickener, also called a soap. Next, there are additives to increase performance characteristics of the grease, such as extreme pressure additives, additives to protect protect the surface of the metal (such as rust and corrosion inhibitors), and additives to protect the grease itself, such as anti-oxidants.

Additionally, the soap, or thickener itself, will have certain desired performance features. If moisture is the primary concern, one should choose a grease where the thickener itself has good water wash out/spray off resistance capabilities (such as an aluminum complex or calcium sulfonate.)  If heat is your main issue then perhaps a clay/bentone soap is the best choice. Additionally, industry has chosen a polyurea thickener for electric motor grease applications because of its stability and oxidation resistance. It is important to note that not all grease based oils or thickeners are compatible, and when mixed, can cause serious issues and ultimately lead to bearing failure.

Finally, we are our own worst enemy when it comes to handling the greases we put into the bearings. We introduce contamination with poor storage and handling practices (such as leaving the lid off the grease keg) or introducing a dirty grease pump into a new container. Be sure to take precautions when handling and applying grease to expensive bearings since unscheduled downtime is very costly. Remember, not all greases, bearing designs or operating conditions are the same: choose your grease wisely!

Download Oil & Grease Storage Best Practices

Are you adding grease to a bearing and not hearing any changes from your ultrasound equipment? If so, start wondering where the grease is going. It is a fact that if grease gets into a bearing the ultrasound decibel will either go down on a bearing that needs grease or go up on a bearing that is already over-lubricated.

Look for a blocked grease tube. Grease may be going into the windings on an electric motor. Do you see grease on the tube of the grease gun? Maybe a greaseable bearing was replaced with a sealed bearing at the motor shop after a repair. These are just some of the things you need to consider if you get no ultrasonic decibel change after injecting grease to a bearing.

Download 5-Step Acoustic Lubrication Procedure

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 was 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 are 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 the 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 the 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 over time. 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 may be required.

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

Download Bearing Storage Best Practices.

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.

Download Oil & Grease Storage Best 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 an 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 operating 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 the 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 presents 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.