How your Equipment Generates a Mathematical Model

July 24, 2014

Guest post by Ray DeHerrera, Mechanical Engineer at Pioneer Engineering

Vibration analyst use multiple tools to predict a potential fault in a machine; from transducers to accelerometers, the toolbox for vibration analysts is continually expanding to allow for more comprehensive and accurate data collection and interpretation. One tool that is absolutely important to the data analysis process is knowing how your equipment processes data. Vibration analysts needs to know how results are being derived from multiple calculations within your equipment. This allows for the development an efficient collection history that will produce more accurate results.

The calculations attempt to translate data banks into a model that can then explain the events occurring inside of your equipment. Often times the computer processed model may develop imaginary information, thus leading to more questions than answers. With basic background and knowledge of variables that may affect your post processed data, your questions will start to be answered.

To introduce the initial creation of our mathematical model that is displayed upon our data collector or computer screen, (such as the time wave form or spectrum) we will explore commonly used hardware such as the transducer. In general the function of the transducer is convert one form of energy to another. A commonly used transducer for case mounted readings is an accelerometer. The accelerometer mimics mechanical vibrations to produce a usable signal. The usable signal is so small that typically an internal amplifier will be needed for your data collector to harness the information. This process is the initial creation of our mathematical model of data, which has been created from a response of a mechanical device (transducer) sitting upon a machine and is now being converted to a digital signal that has been amplified.

Now our signal must be stored for further analyzing. There are a number of vibration collector types and manufactures. The collector is very similar to a computer giving it the ability to quickly process the original signal into various mathematical models. One must take the time to do their research before purchasing a collector and the associated software. Many desired post processing and collection capabilities maybe limited such as sampling rates. With a good collector and setup your mathematical models will be accurate. The accuracy and consistency in your collections is key when managing your periodic collections.

With the basic knowledge of how your equipment generates your post processed model will make your time more efficient and your results accurate. The analyst will be able to identify data that is imaginary and pick out what is real. Take the time to understand your hardware and how your computer generates each model.

 

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Do you have duplicate data in your OMNITREND software database?

July 22, 2014

Have you ever collected data and uploaded the data back into OMNITREND only to realize that you have duplicate data in your database? As a technician, you are pressed for time and your boss needs that report like yesterday. Every so often, when uploading the data you can get distracted by other people or from trying to juggle too many things at once, and you inadvertently upload the data twice.

You can delete the duplicated data without having to delete each one-by-one! Here’s how:
• Click Tools
• Select Report
• Select OMNITREND Web
• Click OK
• Click Database
• Select Database Utilities
• Select Data cleanup
• Once the data cleanup is complete click Close
• In OMNITREND click Database
• Select Database Utilities
• Select Compact & Repair

Once the Compact & Repair process is complete you can go into Machinery Manager, drill down into you database, select the task and then click the Edit Meas. Data tab on the right hand side of the screen, and you will notice the duplicate data has been deleted.

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Reliability Improvement – The Next Step after Condition Monitoring

July 17, 2014

Guest post by Mitch Stansloski, P.E., PhD., Founder and President of Pioneer Engineering

I find that in today’s economy, many of our clients have added, or are attempting to implement, an effective condition based maintenance program. These clients understand the value of this type of program over and above the traditional time-based maintenance strategies. However, it is important to note that if a program stops at this step, it is unlikely that there will be significant improvement in overall reliability or a large reduction in maintenance costs.

This may sound a bit shocking, but based on my 26 years of maintenance and reliability experience, it is absolutely true. Think about it this way: Using condition monitoring to find defects early will not reduce the number of malfunctions that would have occurred if the technology had not been applied. It will give the user time to prepare for the repair, which will save some unplanned downtime, and it will likely reduce the severity of the failure resulting in less repair cost as well. However, decreasing unplanned downtime doesn’t improve reliability, it only improves availability, which is not as valuable. In addition, the costs savings that result from a more minor repair will be offset by the costs of implementing the technology (e.g. instrumentation, software, computers, maintenance fees, etc.) and the manpower to operate it.

In order to improve reliability, the program needs to add steps which focus on reliability improvement. Rather than stopping at diagnosing and replacing a defective bearing for instance, the user needs to identify a root cause for the premature failure. Then the user needs to change how the asset is managed in order to prevent recurrence. If these steps aren’t completed, the replacement part will likely see the same shortened life. Changes to asset management could include revisions to:

  • Installation and setup procedures
  • Maintenance procedures
  • Operating procedures
  • Purchasing specifications
  • Spare parts requirements

Taking these next steps can move a “parts swapping program” facilitated by high tech condition monitoring into a true reliability improvement program.

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The value of wireless vibration monitoring

July 15, 2014

A US manufacturer of chemical products and food supplements has recently experienced an increase in demand for the products they manufacture. To maintain and supply that increased demand, they have increased their reliability efforts. They have done so by re-evaluating their current vibration analysis program and the negative impact recently experienced with unplanned downtime.

After careful analysis of the risk factors preventing their overall business goals from being achieved, the company reached out to LUDECA for a viable solution to their current problems. We installed a VIBCONNECT RF wireless condition monitoring solution. The installation was quite challenging, because the units to be monitored were located three stories high and the control center is about 600 feet in length with hurricane proof walls. The VIBCONNECT wireless system not only monitored overall data, spectral and waveform data continuously every 30 minutes, but also enabled the facility to identify two bearing failures on an important motor-blower set.

Vibconnect RF install

Is your company faced with the same challenges?  Is your vibration program catching the failures on all your equipment?  Are processes being stopped and demand not being met?  A proper condition monitoring and reliability centered effort will always provide a positive return on investment.

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Machine Lubrication – Where to Start and How to Maintain

July 10, 2014

Guest post by Brad Loucks, Mechanical Engineer at Pioneer Engineering

When discussing machine lubrication techniques and associated maintenance tasks with industry personnel, I often hear the same story; “Once a month, we fill it up until it’s full.”  This story can unfold further to reveal that every piece of machinery under such a program receives the same type of lubricant with no considerations made to temperature change, operating conditions, load requirements, and duty cycle.  Technology has come a long way over the past several decades in every corner of the modern world and machine lubrication and oil analysis is no exception to this evolution.  It has been discovered that choosing the right lubricant for the application significantly prolongs machine life and maintains the overall health of rotating equipment in use today.

To further illustrate this point, just consider how much thought is given to the type of oil used in your car.  You won’t find a can of automobile oil in the store that is simply labeled, “Oil”.  Instead, you will find several types of oil that are specifically designed to resist large viscosity changes with changing temperature.  The ability to resist significant viscosity change is depicted using the nomenclature, “10W-30”, or “5W-40”, etc.  A common misconception is that the “W” stands for weight.  Instead, the “W” stands for “winter”, and the number that precedes it represents the oil’s ability to resist thickening when the temperature is 0° Fahrenheit.  Similarly, the second number represents the oil’s ability to resist thinning in an environment where the temperature is 100° Fahrenheit.

As you can see, operating environment and temperature play a big role in choosing the right lubrication to extend the life of an automobile engine.  In an industrial setting, machine lubrication plays an even larger role with proportional consequences and benefits to the amount of thought and detail given to choosing the right lubrication.

Recent advancements in technology now provide us with addition tools to collect and analyze oil samples in rotating machinery.  In doing so, maintenance technicians are able to better understand the present health of their equipment as well as make determinations for further maintenance tasks to be performed.  The difference between this story and the “Once a month, we fill it up until it’s full” story, is that we now have the ability to schedule maintenance tasks based on condition, instead of relying solely on a time trigger.  A proper machine lubrication program enables us to recognize the root causes of machinery failure due to improper lubrication.  A successful lubrication program also incorporates methods in identifying lubricant contamination and implements the best practices in lubricant storage, handling, and dispensing.  By introducing these condition-based methods of scheduling maintenance tasks, machinery health is better managed, saving time and money.

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What do pancakes and your reliability efforts have in common?

July 8, 2014

Just because you pour syrup on it don’t make it a pancake!

Certain ingredients are required to make a reliability program that is desirable, meaningful and sustainable. The minimum ingredients are:

  1. Equipment criticality rankings to recognize where to correctly apply maintenance and reliability efforts.
  2. Understanding what components (bearings, valves, switches, etc.) lead to functional failures in the equipment.
  3. Applying the proper mixture of inspection-based, time-based and condition monitoring-based efforts to mitigate conditional changes before they result in unwanted equipment failures.
  4. Make sure equipment is installed correctly to start with so equipment reliability issues are not introduced from the get-go.
  5. Ensure that equipment is designed to be reliable.
  6. Create proper metrics to verify performance.
  7. Do the work!

Unfortunately, many facilities often apply incorrect methods that do not result in the desired reliability results. Basically, they pour syrup (do the wrong fundamental things) on their equipment and call the result a pancake (reliability). Make sure your facility is applying the correct mixture of efforts to create the real result desired.

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