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Condition Monitoring Expert Tip #5 by Mobius Institute
Now this is a tricky question to answer… We have a few contenders: high frequency vibration analysis, regular vibration analysis, ultrasound, oil analysis, wear particle analysis, and infrared analysis. Let’s start by ruling a few of them out.

Infrared analysis is used to detect heat in a bearing, which is a late stage fault condition, so that’s not your best option. Regular oil analysis can detect the presence of the wear metals within the bearing, but wear particle analysis is a better tool for that. Regular vibration analysis (i.e. velocity spectra) provide very clear indications of bearing faults, however the high-frequency detection techniques provide an earlier warning. That leaves high-frequency vibration analysis, ultrasound, and wear particle analysis.

Ultrasound is easiest to use. Push the probe against the bearing and listen carefully and you will hear if the bearing is in distress. (You can also record and analyze a waveform, but now you may as well be performing vibration analysis). Many would argue that high-frequency vibration analysis (such as enveloping, PeakVue, shock pulse, and others) provide a clearer indication of the nature and the severity of the fault. But it does require more training and potentially a more expensive system to perform the collection and analysis.

And that leaves wear particle analysis. Let’s just say that if you own critical gearboxes, you absolutely must perform wear particle analysis. Performed correctly, you will detect the first signs of wear, and complex gearboxes provide a greater challenge for the vibration analyst and the ultrasound tools.

Although I haven’t really answered the question, I am hoping to have put you in a position to make the right decision for your situation.
Thank you Mobius Institute for this valuable tip!

by Yolanda Lopez

I often hear the question, “what can I detect with ultrasound?”. The fact is, ultrasound is such a versatile condition monitoring technology we tend to ask it to do things beyond its capabilities. And that’s fine because I firmly believe every technology should be pushed beyond its limits. It’s how we get better.
But to help answer the question, “what can I detect?”, I ask a simple question in return. Is your application FIT?
Now you’re asking “what does he mean by is it FIT”?
Let me explain. FIT is an acronym for Friction, Impacting, and Turbulence. Basically, if the defect you are searching for generates any of these three phenomena, then ultrasound is a solution FIT to solve your problem.
Let’s try a super easy example. You are tasked with finding compressed air leaks in your factory. Air lines run every which way throughout your deafeningly noisy plant so you can’t hear the leaks. You could run your hand along all the pipes and anywhere you feel cool air rushing out you’d know you found a leak. Or you could spray soapy water on the pipe joints and look for bubbles. A third solution could be to wait for a plant shutdown and listen for the turbulent flow of air leaks when everything is quiet.

The BEST solution is to ask, “do compressed air leaks produce Friction, Impacting, or Turbulence?”. That’s it! Due to the difference in pressure on either side of the compressed air line, anywhere there is a leak there is turbulent flow. Ultrasound detectors are really good at detecting turbulent flow in high noise environments. There’s no need to run your hand along the pipe, reach for the bubble solution, or wait for a shutdown. Go grab your SDT Detector and start tagging leaks today.

by Allan Rienstra - SDT Ultrasound Solutions

Rotating equipment produces a sound (ultrasonic) signature during operation. This signature can be measured and trended over time. As the machine components begin to fail a change in the ultrasonic signature will occur. The change in sound level can be used to alarm that could be related to lubrication or bearing damage. A key factor to using an ultrasound tool successfully to determine machine health is collecting the measurements at the same location every time. The first step is to identify a measurement test point for each bearing to be monitored. One method for data collection is to use a magnet that should be attached to a metal pad epoxied to the measurement location. The use of a magnet and mounting pad will allow for repeatable and consistent data for accurate trending and alarming. If access to measurement locations is restricted, then a sensor can be permanently installed so that measurements can be taken remotely. Ultrasound is an extremely valuable tool which can be used to detect bearing problems with slow speed applications.
Ultrasound is an important part of any reliability based condition monitoring program and can provide early warning of mechanical failure. This early warning can lead to reduced downtime and increased plant reliability.

by Dave Leach CRL CMRT CMRP

As Published by COMPRESSORtech2 Magazine October 2016 issue
by Karl Hoffower – Condition Monitoring and Reliability Expert for Failure Prevention Associates

Combining ultrasound and vibration sensing adds precision to recip valve analyses

Over the past decade, ultrasonic condition monitoring of reciprocal compressor valves has become more widely known. However, it does not seem to be widely used.
Ultrasonic testing measures high-frequency sound waves, well above the range of human hearing. These ultrasound devices record the high-frequency signals for analysis later. Trending valve cap temperatures is the most common condition monitoring technique for monitoring
compressor valve health.
Ultrasonic testing of compressor valves and vibration monitoring of rotating components are an informative, preventative-maintenance practice. Compressor valve deficiencies with opening, closing or leaking may be diagnosed using the ultrasound recording functions.
Steven Schultheis, a Shell Oil Co. engineer, addressed the issue in a paper presented at the 36th Turbomachinery Symposium in Houston in 2007.
“Trending valve temperatures have proven to be valuable in identifying individual valve problems, but are most effective if the measurement is made in a thermowell in the valve cover.” Schultheis wrote. “Ultrasound has proven to be the preferred approach to analysis of valve condition.”
Failure Prevention Associates completed an experiment with a major midstream gas transmission company to see if this type of condition monitoring tool can effectively find fault conditions well before other technology used.
Ultrasound meters (such as the SDT270 from SDT Ultrasound Solutions) have digital readouts that indicate the level of ultrasound detected. These devices have been used for decades to “hear” air, gas and vacuum leaks. The intensity or amplitude of the signal is expressed in decibels — microvolts. (dB[A] μV). The dB(A) is a common intensity unit for sound intensity; μV designates the engineering reference unit being used with a piezoelectric sensor.
Converting an airborne ultrasound detector with a contact sensor allows a technician to monitor what is happening inside a machine, whether it is a bearing, steam trap, or valve.
Ultrasound detectors are designed operate in a specific and narrow frequency band. Then through “heterodyning” step high frequency sounds down into an audible format that the technician can hear though headphones. During the heterodyning process the quality and characteristic of the original ultrasound signal is preserved.
Read full article complementary-condition-monitoring-boosts-reliability-article

by Yolanda Lopez

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

July 2016 – Flow Control Magazine
PR-SDT_200_steam-trap
Maintaining the health of the assets that make up a steam system brings benefits that are measured by cost reduction, improved product quality and decreased risk to safety. When employees undertake a project that delivers on goals like these, a fourth win is returned by default — improved reliability culture.
When steam system health is ignored, components degrade and efficiency erodes. Over time the system reaches a point where it is no longer able to deliver on its engineered purpose. The maintenance manager’s phone rings. Production needs a fix, and they need it fast. Now it is time to fight fires again.
Which scenario does an organization pursue? Should it pursue the reactive one or the calm, planned approach that sees problems before they emerge, reaps the benefits of cumulative cost savings, has impeccable safety records, and a culture of motivated and artistic employees eager to change their world?
Read the full article: Creating reliable steam systems with ultrasound to better understand the importance of monitoring the condition of a steam system to then act upon the data.

by Allan Rienstra - SDT Ultrasound Solutions

March 2016 · Empowering Pumps Magazine
“Work smarter, not harder” is a statement we have all heard before, but who has the time to think about smarter ways to work when there is so much work to be done? Some maintenance professionals are so busy trying to keep their operation running smoothly that they often address equipment issues “reactively”. This might make maintenance teams feel more like “firemen” as they respond to in-the-moment needs. So how does a company become less “reactive” and more “proactive”?
Read the full article: Maximize Uptime with Asset Condition Management to better understand the key components of an Asset Condition Management (ACM) Program and how core technologies like Alignment, Balancing, Vibration Analysis, and Ultrasound Testing can help you increase uptime.

by Dave Leach CRL CMRT CMRP

Friction is all around us. Without it we would have difficulty to walk, run, or even stand. We need friction to drive our cars and fly our airplanes; and we need friction for our motors to drive pumps and our pumps to push product. So when it comes to our plant assets, friction is both friend and foe.
Lubrication of rolling element bearings is one of the most misunderstood tasks in industry. Can it be true that 40% of bearings never live to their engineered life cycle and bad lubrication practices are a leading cause?
To achieve optimal lubrication we must know:

  • When a bearing needs new grease
  • What quantity of new grease is required
  • And how much is TOO MUCH!

Acoustic Lubrication with ultrasound testing is the technology of choice for Lube-Techs who want to avoid these three common mistakes:
Three Mistakes to Avoid When Lubricating Bearings:

  1. Lubricating based on TIME instead of CONDITION
  2. Over or under lubricating the bearing
  3. Using low quality “Listen-only” ultrasound instruments

To Hear More about implementing a world-class ultrasound greasing program, download Ultrasound Lube Technician Handbook.

by Allan Rienstra - SDT Ultrasound Solutions

Asset Condition ManagementTwo industry leaders of Asset Condition Management technologies for Reliability are joining forces. SDT is thrilled to announce the appointment of LUDECA as exclusive distributor for their portable and online ultrasound condition monitoring technologies in the United States.
SDT’s Director of Business Development Allan Rienstra said, “This strategic partnership is a logical step for two companies whose philosophies are already so closely aligned. Both SDT and LUDECA are approved Reliability Leadership Institute (RLI) Mapped Services and Training (MSAT) Providers. This partnership will deliver significant value to customers through the leveraging of LUDECA’s knowledge and experience.”
Frank Seidenthal, President of LUDECA said, “We are excited by the opportunity to affiliate ourselves with a global ultrasound technology leader such as SDT. SDT’s reputation for producing quality, dependable ultrasound solutions marries well with our vision to enhance our Asset Condition Management product palette.”
SDT develops ultrasound technology that provides industry with a greater understanding about the health of their factory. Their ultrasound condition monitoring solutions help predict failures, control energy costs, and improve product quality. LUDECA is a premier provider of reliability solutions and technologies.
Their years of experience and wealth of knowledge make it possible to offer their customers the very best service and support. They remain the leading supplier of alignment, vibration, and condition monitoring systems to industry.

by Ana Maria Delgado, CRL