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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.

Alarms can save time and assist in the notification of impending issues when analyzing vibration data within your Condition Monitoring software. Of course, the correct alarms must be set in order for the analyst to perform his or her job correctly. Too many times the incorrect levels are set for alarms causing a machine to either be constantly in alarm or for the monitored conditions never to reach the required levels to alert the analyst of an issue that should be alerted.

OMNITREND® software has many different alarms that can be configured to assist the analyst in performing their job. Over time the running condition of a machine will change and it is important to make certain that the alarms are also checked and tweaked if needed. An alarm value might need to be changed many times over the life of a machine.

OMNITREND has a feature that allows the end-user to view the collected data and adjust or set alarms according to the machines’ vibration levels. These “smart alarms” should be set after collecting data for at least three months. The three-month period allows the analyst to view how that machine has operated over that time period.

The ability to display many different data readings at once on the same screen is provided. This allows for smart alarms to be configured using the vibration levels from the machine.   Do remember that a machine’s vibration signature will change over time. Be certain to update your alarms with that information in mind.

If you have any questions or need assistance configuring alarms within OMNITREND please contact us. Our hardware and software support is offered at no charge to our valued customers.

What are some of the most common techniques that should be used every day in a vibration analysis program?

1. Spectrum Analysis
   

   Spectrum Analysis is used to help identify the normal operating frequencies of a machine. Additionally,  the defect frequencies and their characteristics can be routinely identified.

2. Waveform Analysis
   

   Waveforms are one of the most overlook analysis tools. Waveforms can be used to identify fault patterns of equipment defects and help determine the severity of the defect.

3. Trend Analysis
   

   Trend Analysis is a critical part of any vibration analysis or condition monitoring program. Trend analysis will help identify fault trends in equipment that may have gone unnoticed otherwise. Also, trend analysis can be used to help identify the severity and rate of progression of identified fault conditions.

4. Band Alarming
   

   Carving up the entire spectral range into significant bands and setting alarms to indicate when a problem might be beginning is a good way to optimize the time of analysts and the efficiency of a vibration analysis program. This method can prevent fault conditions from being overlooked.

5. Shock Pulse
   

   Shock Pulse is a way of harnessing the resonant properties of sensors to gain valuable defect information. This method can be used for early warning of bearing defects and to identify lubrication-related issues.

6. Envelope Demodulation
   

   Enveloping is a generally valuable early detection method for anti-friction bearing defects and specifically very valuable for detecting such flaws in low and very low-speed equipment.

7. Phase Analysis
   

   Phase analysis can be incorporated into everyday route data collection. This data can be used to distinguish between different faults that may have similar characteristics.

Why does so much ‘stuff’ fall between the cracks that exist between data and information. So often we see a highly trained analyst with a tremendous amount of data working with a manager who takes very little information from the data. There is obviously a communication breakdown but who is to blame. Is it the analyst for not clearly interpreting what the data –the squiggly lines–  are telling us? Or is it the manager’s fault for not understanding what he’s seeing. The reality is that the fault lies with both of them.

I know of some analysts who believe that their role is to take readings and supply them – with a little interpretation- to the maintenance manager. I also know some maintenance managers who when faced with this situation merely file away the reports. Obviously, neither is right but neither has bothered to take the time to make sure that they clearly understand what the purpose of the whole exercise is.

As a plant maintenance manager, I didn’t know the intricacies and nuances of spectrum analysis or waterfalls or acceleration enveloping – I didn’t need to! That’s what the analyst was there for,  but what I did need to do was communicate clearly to the analyst what it was that I wanted from the exercise. For me it was fairly simple – I needed to have enough information to make a more informed decision. That is really the purpose of any measures that we make so I always made a point of clearly explaining this to the analyst. I needed to know if there were any imminent failures or if there were dramatic changes in the trends,  what the implications of the changes were, and how fast the deterioration was taking place (even though we call it predictive maintenance, exact predictions are very difficult).

The analysts I liked working with were the insistent persistent ones – the ones who would not leave until they were sure I got the message. Many people would have considered them a pain – but they were the ones I wanted on my team as they felt the same sort of ownership that I did. I guess that’s the key to it all – ownership – as along with the ownership, there is the pride and success that you share with every good call with every failure mitigated. But this only happens when there is clear communication of the purpose, goals, and expectations. So don’t forget – Communicate, Communicate, Communicate

Thanks to Cliff Williams, Author of People – A Reliability Success Story, for sharing his expertise with us.
 

It is a good idea to complete a few pre-alignment steps prior to conducting any alignment activity.  For instance:

1. Verify a possible misalignment condition by using a condition monitoring technology such as vibration analysis or thermography when possible.  This will help to identify the type of misalignment condition that is present,  and any other conditions that could prevent a successful alignment. This may prevent unneeded work activity.
2. Conduct a visual inspection to identify foundation deterioration,  grout quality issues, broken bolts, cracks in the machine feet or base, etc.  These issues should be corrected before any alignment activity is started.
3. You may wish to take a current power consumption and vibration reading on the equipment prior to any alignment activity and another set of readings after the machine has been properly aligned.  This will document reductions in harmful vibration as well as the energy required to operate the equipment resulting from improved alignment.
4. Consideration should be given to thermal growth.  Accurate thermal growth values should be determined and used during the alignment process.  This will help ensure that the equipment is properly aligned during normal operating conditions.

Often,  “plant floor” realities can create a problem when planning shutdowns because sometimes power transmission components like sprockets, idler rolls, sheaves, timing belt wheels, couplings, etc. can’t be inspected properly without shutting down an entire process. In such cases, there are times when a simple “visual” inspection would be enough to reveal the need to order a new part and have it ready. If this might be the case for you, take along a good strobe light, and if you can get close enough safely, “freeze” the coupling, sheave, sprocket, or whatever the component, while in motion to get a good look at it. By carefully varying the strobe timing, you can cause a component that is spinning at 3600 RPM to rotate at any speed you like (say a half RPM) and inspect all of it—every tooth of the gear, every part of the belt or sheave. If flaws are obvious, you may have just saved your company some downtime, not to mention a potential catastrophic failure!

CAUTION! Remember that with strobe lights the eye is deceived into believing that something is not moving, or moving very slowly, when in fact it is moving very fast. Do not ever forget this and NEVER reach out to touch the part you are inspecting!

Every day more and more of the maintenance and reliability community is transitioning into using tools such as LinkedIn,  Twitter, blogs, and wikis. There is now a wealth of information out there for those who know how to find it. In his presentation “Who Gives a “Twitter” About Being “LinkedIn” to Reliability? Ways to Improve Plant Reliability with the Internet” at the SMRP-2013 Conference in Indianapolis, Shon Isenhour discussed what these smart people are doing, how they are doing it, and what they are gaining for their efforts.

Shon gave us real examples of problems solved via the Internet and how others can join in to find solutions to their challenges. He wrapped up his session by providing 10 ways to put the Internet to use immediately within your plant. Here they are, in no particular order:

1. For RCA preparation prior to getting the team together, pull equipment documentation and any history available via Google.
2. Search bulletin boards and user group pages for common equipment failures others are experiencing using Google. Verify that these are part of your Equipment Maintenance Plan (EMP) and your Reliability Centered Maintenance (RCM) and Failure Mode and Effects Analysis (FMEA) efforts.
3. Locate spare parts for obsolete equipment via eBay and Google.
4. Locate new vendors and service centers for existing parts via Google.
5. Identify physical defects with pictures of similar failures from Google images.
6. Find equipment vendors’ websites via Google… It is not always so obvious.
7. Read about additional vendor, equipment, part, or product characteristics information on Wikipedia prior to and during an RCA.
8. Follow your common vendors on Twitter to be in the loop with their most recent product releases and updates.
9. Read the blogs of people interested in the same topics or that deal with the same issues you face.
10. Read the various trade publication websites for articles that target the problems you are facing.

Bonus: If you don’t find the answer in any of these places, then post your question to LinkedIn and see what you get.

Thanks to Shon Isenhour, CMRP with Allied Reliability Group for sharing his presentation and knowledge with us.

Visit Shon’s Blog at: www.reliabilitynow.com
Join the LUDECA Machinery Alignment | Vibration | Balancing LinkedIn Group
Follow LUDECA on Twitter

One thing regarding Pre-Cuts is that the 4 thicker thicknesses (in all sizes),  .050″, .075″, .100″, & .125″ are NOMINAL thicknesses, so the marked value may NOT necessarily be the actual thickness; therefore you MUST measure them to be certain that you know the actual thickness.

There are many different brands on the market. Some have closer tolerances to the nominal thickness than others. Some are very “liberal” in the actual vs marked thickness. Some brands mark them with the actual value to the nearest .001″ (example .102″ or .076″ vs. .100″ or .075″. I have seen some that are marked to the nominal thickness to be off by as much as .005″ from the marked nominal value.

This is important to know because if you “assume” that the marked thickness is the actual thickness, you may be adding or removing the wrong amount when making shim changes, or creating a Soft Foot condition. It is always a good idea to measure each of the four thickest shims.

Another thing to look at with Pre-Cuts is the edges of each shim. One Brand CONSISTENTLY has a ridge on either side; I have measured this ridge to be as much as .005″ thicker on the edge than the rest of the shim. This shim will produce a Soft Foot that you can’t get rid of on all four feet. It’s like inserting leaf springs under the machine’s feet.

Conclusion: Pre-Cut shims’ quality can vary greatly. Poor quality shims can make the alignment process very difficult. Be careful which one(s) you select!

Thanks to Roy Loop with The Rueck Company for this valuable post.

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.

You’re 17 times more likely to introduce defects during equipment startup than during normal equipment operation.  Additionally,  over 90% of rotating equipment has defects at startup that result in premature equipment failures.

Misalignment and unbalance are two of the most commonly overlooked conditions that lead to the unwanted statistical results referenced above.  Misalignment in equipment leads to increased vibration levels, bearing failures, coupling wear, seal failures, shaft fatigue, increased power consumption, and other negative effects.

Unbalance in equipment can introduce structural related issues, bearing defects, and other issues. Both conditions can create unwelcome safety concerns.  Additionally, both conditions can be present on the same equipment, and working in concert can, unfortunately, amplify the referenced failure conditions.

So, how do you prevent misalignment and unbalance conditions from making your equipment part of these negative statistics and placing your company at financial risk?  The answer is to apply condition monitoring technology and procedures such as laser alignment, equipment balancing, and vibration analysis to your equipment.  These condition monitoring activities will lead to reduced equipment downtime, reduced equipment failures, improved safety, reduced financial risks, increased equipment uptime, lower operating costs, and increased profits for stakeholders.

When rotating hard-to-turn shafts by means of straps,  pipe wrenches, chain hoists, or any other means, you could be deflecting the shaft. This can cause significant alignment and repeatability problems to occur, making the task of collecting accurate alignment readings almost impossible. The problem is easy to overcome, though. Simply switch your ROTALIGN® ULTRA to Multipoint or Static measurement mode instead of using Continuous Sweep mode. Your readings will be taken while the shafts are stationary and with no external forces applied.

Between the two measurement modes, multipoint will be the measurement mode of choice. The jerky, starting/stopping motion you will most likely be experiencing will make it very difficult to stop at the specific angles needed for static mode.

ROTALIGN® ULTRA will always suggest the ideal move,  but in the real world,  as we all know, that’s rarely how things work out. It may tell you to shim an impossible amount (say by asking you to remove more shims than what you have under the foot) or require a horizontal move in a direction you are bolt-bound in. Maybe you have an alternative idea of how to achieve the alignment and want to test what the outcome will be. These theoretical moves can easily be tested using the Move Simulator in the ROTALIGN ULTRA, without actually having to move the machines! Simply input the shim amount you want to try at each foot or the horizontal move you want to test. You will instantly see the outcome. On systems without the Move Simulator feature, input your proposed corrections as thermal growth values and return to the results screen. Your results screen will now show what would happen if those corrections were effected. If you opt for the second option, be sure to remove the fictitious thermal growth values before taking more readings and actually performing corrections.

Good condition monitoring software will have capabilities that allow importing of critical process data into the CM database.  Information such as temperatures,  pressures, equipment speed, etc., are very important to the vibration analyst or other CM analyst.  This information provides additional parameters to help the analyst understand and confirm the results uncovered during their analysis.

The most important thing that can be said about securely mounting bracketing is this: Whatever you attach the bracket to MUST be rigid to the shaft when you are not attaching to the shaft itself. When the bracket is secured and the laser/emitter is attached to it,  rotating the shaft causes the bracket to rotate along with the laser like the spoke of a wheel. Regardless of the laser’s distance from the shaft centerline, as long as everything is tight, the invisible circle that the laser traces as it is rotated has the same rotational centerline as the shaft. Make sure that everything is tight.

When a facility goes into a planned outage,  many events needed to happen before the company gets to this point.

The following are some interesting facts and activities a plant will undergo before an outage:
• Planning for a major outage begins when the previous outage is completed.

• Planning and scheduling play a major role. Prioritizing which jobs need to be completed,  and in which order, and obtaining the necessary permits and work orders.

• Most of the maintenance budget of a facility is spent on outages. With proper planning and scheduling, costs can be reduced, rather than reacting to imminent problems.

• Several factors dictate when an outage will take place: Weather, the flow of incoming raw material, demand for product/service, consensus with the local utility, cost, and manpower.

• Preparing or ordering auxiliary equipment and/or replacement components. Identifying lead times helps with scheduling.

• Preparing scaffolding permits and crew will help indicate the length of the outage.

• In most cases, operations will control the work, and maintenance performs it.

• Determining the need for contract work, and in-house work. This will identify the available manpower and labor hours.

• Scheduling visits from manufacturer’s representative for critical equipment. This will help with warranty issues, and ordering necessary components.

• Safety programs and procedures must be implemented.

• Implementing an RCM program may help more planned work and fewer unexpected outages.

• Identify how many shifts will work during the outage, and hire the proper crew.

For many vibration analysts,  a magnet is the point of contact between them,  with all of their sophisticated technology, and the rotating equipment they wish to monitor. This being the case, the magnet and its mounting characteristics occupy a very important position in the scheme of what they do every day, yet this crucial part of their occupation is most often taken for granted.

Check your magnets frequently! Make sure the sensor is securely bonded to the magnet so the least possible interface loss is experienced. If you have to help hold the magnet and sensor onto the equipment, it’s time to get a new magnet. The magnet should be strong enough to support the weight of your cable assembly without rocking at all when the cable is swinging. When your sensor and magnet are not in use, make sure the magnet has something to pull against like a washer or what many analysts have found to be very useful for magnet storage… the side of a metal file cabinet.

During the recent AFPM Reliability & Maintenance Conference and Exhibition in Orlando, FL. Terry O’Hanlon, Publisher of Uptime Magazine and Reliabilityweb.com, gave a speech about proper maintenance practices. One of the subjects was ‘Proper Mounting of Bearings’.

In the late 1960s, one of the large cottonseed processors in Nicaragua had an urgent need for a replacement bearing made by Timken for their oil extraction units.

Not only did I sell them the not readily available industrial bearing from Timken, but I also offered them a FAG Induction Heater for Bearing and/or a DAKE hydraulic press (both products for which we had the representation for Nicaragua) for proper mounting of the expensive bearings. The customer didn’t care for anything else but the bearing. Improper mounting procedure damaged the new cup and cone bearing before it underwent the first revolution on the shaft. The result was a repeat order for another bearing, however this time with a hydraulic press from DAKE.

The revolution in Nicaragua in 1979 brought me to the USA. Again I am selling Bearing Heaters among other maintenance-related tools for predictive and corrective procedures. Unfortunately, it is now easier to sell products that keep manufacturing plants running efficiently in an industrialized country like the USA than in a country of the Third World.
Some use Induction Heaters for Bearings with an electronic temperature probe, others use so-called Tempsticks which melt at a certain temperature and thus indicate that the bearing is ready to be mounted while others wait until the grease of the bearing starts to evaporate creating a certain smell which for them is a sign that the proper temperature has been reached. Bearings should never be heated beyond 120 degrees Centigrade (250° F) because otherwise, it starts to change the metallurgical structure of the bearing.
Not only bearings should be properly heated. Gears, crane wheels, and other industrial components are heat-treated in costly processes which easily go to waste due to unprofessional procedures like using a blowtorch resulting in uncontrollable and uneven heating.

As long as maintenance processes are not brought up to modern standards, and as long as Maintenance Departments in every single industry in our country are not given their due status, and as long as Production and Maintenance don’t act in unison, will we not be able to regain dominance in production.

Proper equipment alignment removes many root causes of equipment failure. Some of the benefits of proper alignment with a laser shaft alignment tool are:

• Reducing vibration levels. Lowering vibration levels in your equipment will result in increased component life for bearings,  seals, couplings, and other components. For example, reducing overall vibration levels in equipment by 10% can increase bearing life by approximately 40%.
• Minimizing coupling wear and failures.
• Minimizing seal failures.
• Reducing the possibility of shaft fatigue and sudden catastrophic failure.
• Reducing power consumption in running equipment.

Every organization claims they have procedures or “checklists” to eliminate self-induced failures or missed steps but are they followed? Are they accurate? Are they written to a sufficient level of detail? Have they ever been reviewed? Do we know the difference and when to use them?

A checklist is a type of informational job aid used to reduce failure by compensating for potential limits of human memory and attention. It helps to ensure consistency and completeness in carrying out a task. Checklists are appropriate for vehicles, mobile equipment, equipment set-ups, equipment or line starts and stops, etc.

A procedure specifies a method for performing a task, it is written to a specification. A procedure is designed to describe who, what, where, when, and why by means of establishing accountability in support of the implementation of that specification. The “How” is further documented in the form of work instructions which further support a procedure by providing a greater level of detail. Procedures are appropriate for Preventive Maintenance (PM), Predictive Maintenance (PdM), equipment rebuilds, refurbishments, or overhauls, corrective maintenance activities, etc.

Both can and should be utilized in support of maintenance activities where applicable.

Thanks to Dave Bertolini with People and Processes, Inc. for this great tip.

With the shift in technology over the last ten years,  it is easier to store pictures, music, and documents on a computer. The computer allows quick access to files and the ability to share them. Of course, with technology there are risks, but most can be minimized. One of the worst things that can happen is for the computer to crash or the hard drive to malfunction, rendering all your files unretrievable. A computer has a lot of ways to duplicate your files, but this is usually thought of too late. Once your computer crashes it is usually too late to make a copy or a backup of your files.

Creating a vibration database takes time and effort to make certain everything is entered correctly for your facility. Once everything is set up correctly, vibration data is collected and transferred into the vibration database. That vibration database is a health history of the machines for which vibration data was collected. Many additional items can also be stored within condition monitoring software such as machine photos, repair invoices, infrared images, and work orders to name just a few. How important is the data that is contained within your database? It is strongly advised that your vibration database be backed up on a regular basis. What constitutes a regular basis? It is suggested to back up your database after any major change. The rule of thumb for backing up a database should be related to how much additional effort would have to be expended in order to get the database back to its current state.

It is very easy to back up your condition monitoring database. A decision will need to be made as to how and where the database will be backed up. If you are running a network version of the condition monitoring software, then in most cases the IT department is backing up the server where this database resides. If you are a standalone user, then the responsibility of backing up the condition monitoring data rests on your shoulders. You should consider copying the database to a flash drive or creating a CD/DVD. Does your IT department have a shared network drive that is being backed up every night? That would also be an excellent place to copy your database.  It is fine to have multiple backups of your database but be certain that the backups are recent and not months or years old.

A regular backup policy can save time, effort, and protect your valuable data. The cost of external data storage is very inexpensive and allows for the vibration database to be backed up too many different media types such as CDs, DVDs, external hard drives, and USB flash drives as examples. Being proactive should not only apply to your maintenance program but should extend to the backing up of your vibration data!