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Condition monitoring is the process of monitoring a parameter of condition in machinery,  such that a significant change is indicative of a developing failure. Ironically most Condition Monitoring Programs often fail and here are some reasons why:

• Inappropriate use of “Low Tech”  or “Low Priced” condition monitoring (CM) technologies
• CM technologies are purchased and results are magically expected to appear
• Use of “Part-Time” personnel for CM efforts
• Insufficient (or no) training provided initially and continually
• Do not establish certification criteria for employees
• Insufficient “LOA” (level of awareness) training to plant employees so that they understand the importance of CM efforts
• Failure to create sufficient collection schedules (routes)
• Apply CM technologies to a limited amount of plant equipment or the wrong equipment
• Over dependent upon a single CM technology
• Improper or outdated alarming criteria
• Improper utilization of the CM technology and software
• Improper database setup
• Poor documentation, reporting, and communication of the results
• No metrics to provide feedback
• No follow-up inspections on repaired equipment
• No acceptance inspections on new equipment, lubricants, etc.

When Condition Monitoring programs fail, equipment reliability fails too. Don’t let your program become another statistic or “flavor of the month”. Use proactive tools like Reliability Centered Maintenance or other techniques to develop a basis for the Condition Monitoring strategies you deploy. Work to ensure that the reasons listed above don’t become your reasons for failure. If you need help, please let us know because we measure our success on your success. What other items would you suggest to achieve and sustain success?

Severity determination is one of the most difficult tasks a vibration analyst faces. Several methods can be used to help identify the severity of defects identified in vibration data.

One method is to consider the amplitude of the defect. This usually works well but does not always correctly identify the severity of the problem. Another method is to look at the G swing (peak-peak value) in the time waveform data that has been collected. An additional method is to trend the data and look for increases in trend values between data collection intervals. The rate of change shown in the trend data can be a very good indicator of the progression of the identified defect.

A combination of methods usually works best to help identify the severity of a defect. However,  it is always best to report the defect condition for repair as soon as it has been identified.  This provides as much time as possible to properly plan and schedule repairs as may be required.

The Reliability Support Team at the Eastern Processing Facility located at Cape Canaveral Air Force Station,  FL,  won Uptime Magazine’s Best Design for Reliability Program award.

During the design phase of their program, the team was challenged with the implementation of Reliability-Centered Maintenance (RCM) principles and Precision and Predictive techniques from construction through commissioning. These have proven to be the most advantageous with regard to failure mode consequence reduction.
Congratulations to Frank Saukel, Garry Pell, and their team for this prestigious award and a job well done!

Program Highlights
1. Eastern Processing achieved Failure Mode Reduction with added redundancy.
2. They redesigned the facilities’ Reverse Osmosis Water System.
3. They performed Asset Prioritization based on safety, environmental, mission impact, and probability of failure studies.
4. They trained technicians and engineers on RCM. In the words of Garry Pell: “Don’t expect to gain tribal knowledge if you don’t invite them into the Teepee. Get your people involved from engineering to safety, from shipping to operations.”
6. They developed all maintenance procedures based on RCM decisions.
7. They identified the Predictive Maintenance (PdM) technologies and tools they needed, met with different vendors at different IMC Conferences, then focused, implemented, and trained on 1 or 2 maintenance and

Condition Monitoring (CM) technologies annually, including:
• Lubrication analysis
• Vibration analysis
• Laser shaft alignment
• Infrared thermography
• Ultraviolet thermography
• Electric signature analysis
• Ultrasound
Many discrepancies were corrected using these PdM and CM technologies. According to Frank Saukel, “Every one of the PdM technologies has paid for themselves.” For instance, they identified misalignment and motor structure resonance conditions using their VIBXPERT® vibration analyzer on several of their water pumps which had been aligned by a contractor.

Every pump was found to be bolt-bound and base-bound. They realigned all their pumps to excellent tolerance with their ROTALIGN® ULTRA laser alignment tool.

They also found and corrected electrical deficiencies with ultraviolet thermography and detected sub-grade piping leaks with ultrasound. Their precision lubrication program included oil analysis, with a resulting reduction in the number of lubricants, minimization of cross-contamination, and implementation of a color-coded system for easy machine identification and the use of accessories to control moisture. Learn more…

When performing an alignment on a machine train with a motor fitted with a sleeve bearing,  it is important to account for the magnetic center of the motor. Failure to do so can cause excessive vibration and premature failure of motor components and the shaft coupling.

If the motor has recently been rebuilt it should come from the motor shop with a magnetic centerline scribed on the shaft. To properly set the shaft coupling gap do the following:

• Determine the correct coupling gap based on the manufacturer’s recommendation. (Note we refer here to the proper installation gap size and its tolerance, not the alignment gap tolerances for angularity.)• Identify the correct scribe mark on the shaft that represents the magnetic center.
• Measure the distance between the scribed mark and the outside bearing housing lip. In the case that the magnetic center scribe mark falls inside the motor housing while at rest, scribe a mark in the rest position.
• While the machine is un-coupled run the motor and estimate the difference between the newly scribed mark and the magnetic center mark. This is the distance that will need to be compensated for when setting the coupling gap.
• Set the coupling gap according to the manufacturer’s recommendation minus the distance measured for the magnet center correction if the mark is outside the bearing housing. Add the difference if the mark is inside the bearing housing. This will provide the proper coupling gap under the normal running condition.

Every person that performs vibration analysis develops their own analysis process.  Suggested steps at a minimum should include:

1. Open the spectrum (FFT) and locate the running speed peak and reset the reference speed to that speed.  Since all induction motors vary in speed based on the load,  this is necessary for accurate analysis, particularly at multiples of running speed.

2. Are there any peaks of interest?

3. Where is the primary energy located?
a. Is it sub-synchronous, synchronous, or non-synchronous?

4. Do the waveform patterns support the peaks in the spectrum (FFT)?

5. Remember that defects follow patterns.  Some defects happen at frequencies less than running speed (sub-synchronous) or at running speed or at multiples of running speed (synchronous), or at frequencies greater than running speed but not at whole integers (non-synchronous).

6. Learn pattern recognition and don’t overlook the obvious.

Learn about our vibration analyzers

MEDIA RELEASE  
The AHR Expo and its co-sponsors,  ASHRAE and AHRI, have recognized our VIBCONNECT® RF wireless condition monitoring system with an HONORABLE MENTION in the BUILDING AUTOMATION Category of the 2013 AHR Expo Innovation Awards Competition. A panel of Industry Professionals, selected for their knowledge and expertise in HVACR, found our VIBCONNECT RF worthy of this recognition. Representing a broad cross-section of the HVACR marketplace, the winning entries were selected in 10 categories and represent the most innovative new products among the thousands that will be displayed at the show. A panel of judges made up of ASHRAE members evaluated the products submitted based on innovation, application, value to the user, and market impact.
Read the official AHR Expo Press Release.
Winners will be honored during the upcoming HVAC event, the 2013 AHR Expo, Dallas, TX – January 28-30. Register today for FREE exhibit hall pass.

We recently ran a poll to find out what the Top Machine Faults are for the attendees of the IMC-2012 International Maintenance Conference. Here are the results,  which came from maintenance and reliability professionals who attended our Learning Lab:

Misalignment: 32%
Bearing Failure: 31%
Unbalance: 18%
Looseness: 16%
Other: 3%

The good news is that all our lab participants were acquainted with our Condition-based Maintenance tools which can help them detect,  prevent and correct all these problems.
It is essential to understand how equipment performs in a facility and to be able to identify these common machine reliability issues before they result in functional failures in your equipment. Payback technologies like vibration analysis, alignment, and balancing when part of a comprehensive condition monitoring program can improve your equipment performance, reduce equipment downtime and minimize risk.

Vibration analysis is the best all-around technology for diagnosing and predicting problems in rotating machinery. Over the years I have seen time and time again where adopters of this technology have saved themselves and their companies countless man-hours and thousands of dollars by getting to the root cause of a problem early on. By analyzing the data,  they are able to schedule their valuable time on the right problem on the right machine long before the problem escalates into a major outage or emergency. But too many companies have not adopted vibration analysis. While it is true that one could spend many years learning the skills of the multiple levels of the vibration analysis disciplines,  it is also true that even a basic understanding of the relationship between the time waveform and the spectrum can yield huge benefits and savings to a new user.

For example, the root cause of most roller bearing/seal failures is either shaft misalignment or rotor imbalance, which can take months to develop. It is also the most common problem analyzed within most facilities in the first two years of vibration analysis implementation. The good news is that misalignment and rotor imbalance are the easiest problems to diagnose by observing a high amplitude 1× running speed frequency in the spectrum. After that, a phase analysis with your analyzer can easily differentiate between misalignment or an imbalance problem and quickly completed without shutting down the machine.

We all know that Rome wasn’t built in a day but we all must start somewhere and just a few days in an analysis class could yield major benefits to new companies.

Thanks to Jay Gensheimer with Solute LLC for this valuable post.

It is All About the Cost!
We have all been there — It is about time to leave for the weekend on a late Friday afternoon,  most of your maintenance staff has already left for the weekend, as you are getting ready to head out, all of the sudden someone runs up to you and says, “We have a problem, one of our assets just failed”. As you hurry off to assess the situation and mentally start thinking of who you can get in touch with to help rectify the situation, you cannot help but wonder to yourself, could this failure have been prevented?

Many people who are involved with the maintenance and operations of critical machine parts know of the benefits of a routine Predictive Maintenance Program and have often attempted to establish a Predictive Maintenance Program (PdM) within their facilities. The problem is, very rarely do the people who know the value of a PdM program have the ability to allocate the required budget to implement a PdM program, and without hard numbers, budgeting for a PdM program can be a hard sell. Here are some ways that one can use to help justify a PdM Program within your facility.

When businesses look at where to allocate their money, they do so with the hope of investing in things that will have the greatest return on investment (ROI). This is understandable because businesses are in business to turn a profit. Oftentimes, others outside of maintenance and operations do not understand the return they will see through a PdM program being implemented. However, with a well-established PdM program, companies can generally see their ROI in less than one year! And, in actuality, the ROI happens more typically within about 6 months’ time. That means the money that it costs to start a program is typically saved by the company within 6 months from implementation.

All plants will have a random failure, but a well-run PdM program will help detect and mitigate many of the potential problems and prevent many unplanned outages on critical assets. Unscheduled downtime is expensive and can result in safety or environmental incidents. Hidden costs from failures can include premium pay, the premium cost for non-stocked spares, and additional regulatory reporting.
Potential savings from a well-run PdM program also include reduced maintenance costs because intervals for periodic preventative maintenance shutdowns can be extended because you know the condition of the machine, and can decide that a PM is not required at the current interval. Also, since machine condition is better known, parts inventories can be reduced and the parts can be sitting on the vendor’s shelf instead of yours.
Put simply, if it costs $1 Million a week to run your plan, a breakdown that results in a plant outage can cost $6000 per hour in downtime plus the cost of repair, overtime, and premium costs of parts not in stock, environmental clean-up, etc. This does not include potential profit from lost sales.

Predictive Maintenance Programs offer the lowest cost with the highest savings for most plants and facilities. With a PdM program established maintenance will be able to detect when an asset is deteriorating ensuring that a spare is ordered and on hand. In addition, the repair can be scheduled during scheduled downtime, so there is no loss in production. In addition, if the company contracts out the PdM program, oftentimes your company can avoid the initial start-up costs associated with starting up a PdM program.

Thanks to our training partner Pioneer Engineering for allowing us to share this article with you.

Every vibration analyst knows that our failures are quickly publicized throughout the facility or corporation. It is amazing how quickly this type of information is transmitted.  This is why most analysts develop a very thick skin or soon find another career path.

It is important to make sure that your successes are publicized as well.  Management should support this effort to increase the awareness of the Condition Monitoring (CM) efforts in your facility.  Save the bearings and other items that are removed from the equipment as a result of your CM efforts.  Keep some of these items around your office to do a “show and tell” when people visit you to criticize your efforts. Consider creating a monthly or quarterly email or newsletter demonstrating your successes.  Publicize your findings in an article or present the findings at a trade show.  Be creative,  but make sure that others are aware of the value that you and the CM technologies you utilize provide. Otherwise, you may find yourself and/or the CM group on the chopping block.

Do you verify the quality of the maintenance work or installation that is completed on your equipment?  You may be surprised to know that failure modes such as bearing defects,  misalignment, etc., can be introduced into your equipment as a result of poor maintenance practices or installation work.

Condition Monitoring (CM) follow-up measurements should be completed after each maintenance repair on your machinery. This will allow you to verify that the equipment was repaired correctly and that no other failure modes were induced as a result of the repair effort or installation of the equipment.
It is a good idea to make CM follow-up measurements a part of the work order. This way the work order cannot be closed until a follow-up measurement with the CM technology (vibration analysis, oil analysis, ultrasonics, motor diagnostics, thermography, etc.) has been completed.  This will help you ensure that your equipment was repaired correctly, installed correctly, and is truly ready for operation.  This results in improved equipment reliability.

Do your analysts use consistent phrases or statements when creating condition monitoring (CM) work orders?  It is very important to convey concise and accurate information with each CM work order. Often times misspelled words,  inaccurate information, or incomplete maintenance steps are included in work orders. A best practice is to determine the most common findings for a specific CM technology and determine what actions should be taken as a result. For example, if vibration analysis identifies unbalance in a fan, a recommendation should be made to clean the fan prior to attempting to balance it. If a CM technology identifies a failure that requires the machine to be removed, then re-alignment may be necessary before the machine is placed back into service. All of these steps and perhaps additional steps should be conveyed by the CM analyst creating the work order.

Creating consistent and detailed steps for common CM problems will avoid forgetting to convey important information to those doing the work. This will help ensure that best practice maintenance is completed on your equipment, things are not forgotten, misspelled words entered, or other common mistakes made.

WATERWORLD • September 2012

The water treatment facility in the City of Fairfield,  Ohio,  uses vibration analysis as part of its condition-monitoring planned/predictive maintenance program to help verify and assure equipment is operating satisfactorily. The Water Treatment Plant processes an average 5.1 mgd for a population of 44,000 people with a customer base of approximately 14,000 accounts.

Public Utilities Superintendent Andreas Eddy initiated the vibration analysis program as part of a cost-savings measure with regard to the “total” operating cost of equipment associated with the water treatment process. The intent was to identify potential equipment problems at an early stage and to allow maintenance work to be performed on a proactive basis.

Vibration data was collected with the VIBXPERT® 2-channel vibration analyzer and plotted with OMNITREND® software by Prueftechnik/Ludeca. The system helped identify a “Severe Mechanical Looseness” problem on a pump installed at a pumping station considered critical to the city’s water system.

Read the entire article Vibration Analysis Helps Identify Pump Problem

Thanks to Ray W. Wonderly of Advanced Maintenance Technologies for sharing this case study with us. Special acknowledgment to Andreas Eddy, Superintendent of Water Treatment Operations for co-authoring and approving this case study.

Many facilities have placed overall vibration data collection devices in the hands of their operators.  The goal is to give the operators and production a tool to help identify equipment problems and the severity of those problems.

The intent of this effort is very good.  However,  the true value of this effort is usually not understood.
First,  generic overall vibration levels can be quite dangerous if not fully understood. Secondly, the actual value of having operators collect vibration data is not usually taken advantage of fully.

Overall vibration levels require the same amount of time for data collection as is required to collect very detailed vibration information on the equipment.  Therefore, the operator should actually collect the overall vibration levels they need while simultaneously collecting detailed information for the vibration analyst to review.  What happens if the operator collects an overall vibration level on a machine and some problem is suspected?  The facility has to invest time and effort for an analyst to revisit the machine and collect enough vibration data to actually verify and analyze the problem.  This means that additional labor is required or the results are diminished.  With the correct vibration hardware, the operator can easily collect the overall vibration values they need as well as the detailed information the analyst needs.  This saves time and money.  What if the activity occurs after hours?  The detailed data collected by the operator could be remotely passed on to the analyst for detailed evaluation.  This saves time and greatly improves the response time from employees and the technologies.   Operators could be used to easily and routinely collect vibration data on much of the equipment for analysis by the vibration group.  This would allow greater equipment coverage by the vibration analysis program, allow the analyst to focus on analysis, and spend less time collecting data.

To summarize, having the operator collect vibration data can be of great value if done the correct way, otherwise, the process can provide inaccurate information and reduced benefits.

PUMPS & SYSTEMS • August 2012

By James Laxson,  Hi-Speed Industrial Services in collaboration with Mike Fitch,  LUDECA, Inc.
In May 2010, an electric motor repair service provider in Little Rock, AR, began a condition monitoring program for a new customer. The customer opted for quarterly data collection.

Read the article Pump Train Component Failure, a briefcase history of a component failure in a nominal 1,800 RPM pump train.

Setting the proper LOR is essential to be able to separate closely spaced defect frequencies.  An example would be a pump with 5 vanes that could generate a “Vane Pass” frequency equal to the number of vanes,  or 5 times rotational speed; if the impeller end of the pump had an SKF 7301BEP bearing, it could have an inner race defect frequency of 4.99 times running speed.  This combination would require a relatively high resolution or LOR in order to have enough detail to separate the defect frequencies of each defect.

Overall values are the most common measurements and calculations used in vibration analysis. The purpose of this measurement and calculation is to identify changes in the condition of the equipment being measured.

Overall measurements are an important tool for the vibration analyst. However,  generic overall values can actually be deceptive if their limitations are not fully understood. Typically, overall vibration values are measured and a calculation based upon the entire frequency range is measured with the vibration data collector.

It is possible for certain frequencies to increase while other frequencies decrease. This is important because these changes are indications of specific machine conditions. The overall value could actually decrease or change very little and give a false indication of the machine’s health.

Band alarms and band analysis is the best vibration method to indicate changes in the condition of your equipment. Specific bands can be easily created, measured, and trended around the specific failure modes in the equipment such as bearings, misalignment, unbalance, and many more. This type of information can alert you much more accurately of failure conditions in your equipment versus generic overall measurements and calculations.

An air conditioning and heating systems manufacturer in Texas is challenged to continue providing the industry with leading products,  while meeting high-reliability standards, maintaining affordable prices, and meeting increasing worldwide demand for the products they manufacture.  All of this must be done in a way that provides the expected financial return for stakeholders.  An internal evaluation was completed to determine how to achieve and continually meet these goals.  It was determined that the negative consequences of unplanned downtime, high production costs, inability to increase production capacity and product quality issues were putting these goals at risk.  The goal of the facility is to maintain equipment uptime and availability at greater than 90%.

The final analysis revealed that additional reliability efforts would reduce the risk factors preventing the achievement of their business goals. As a result, the company understood that an investment in Condition Monitoring was required. Consequently, an investment in our VIBXPERT® II portable and VIBNODE® online vibration analysis systems was made.  The company decided to install permanently mounted sensors due to equipment accessibility issues.  A LUDECA CM Engineer completed a start-up and commissioning process to help maximize the return on this effort for the customer.  The OMNITREND® software and vibration analysis equipment provided by LUDECA has already enabled the facility to identify a number of bearing problems and other reliability issues preventing their goals from being achieved.

Does your company have the same challenges and results expectations as those described above?  What is your facility doing to improve reliability, product quality, production capacity, and the financial return for stakeholders?  How does your company mitigate risk factors that prevent your goals from being achieved?  A proper investment in Condition Monitoring and reliability-centered efforts will continually provide a positive return on the investment.  This will help your company achieve positive financial and competitive goals like the company above.

Visual inspections of equipment should always be completed during vibration data collection or the collection of any type of condition monitoring (CM) data. This important function is often overlooked and valuable information on the condition of your equipment is lost.

Looseness and many other conditions are commonly found as a result of a vibration analysis program. The source of these conditions should be corrected to improve the equipment’s reliability. Visual inspections can easily be completed on the machine while the data collector is acquiring the data. The visual inspection may reveal the source of these equipment issues. This will save time because future efforts will not be required to determine the cause of the issue.

Visual inspections may provide a confirmation to the analyst of the problem(s) uncovered by the vibration analysis program or other CM technology. It is important to diagnose and confirm problems to ensure accuracy in your CM efforts. Visual inspections may often provide the confirmation opportunity needed.

Safety issues are often uncovered by these routine visual inspections and can be corrected before an employee is injured. This could save a life and the resulting return on the investment is priceless!

One of the most overlooked features of a good vibration data collector is the ability to enter important process information such as temperatures,  pressures,  equipment lubrication levels, equipment speed, and much more.

Documentation of process data is important for your production department. This information is important to the Condition Monitoring (CM) Analyst as well.  Changes in process data may explain why the vibration amplitude levels or other CM conditions have changed.

Many facilities struggle with the ability to record and store process-related data. A good vibration data collector will have the ability to record and store this type of information.  In fact, routes can be created for operators to guide them through the routine acquisition of this information. Vibration data can be acquired by the operators as well. This could provide additional value-added time in your facility.

This data can be easily stored to meet the documentation requirements of your facility and trended to provide increased analysis opportunities that may otherwise go overlooked.