October 02, 2008
Balancing Tip
The best balancing tip is using a Strobe Light Vibration Analyzer / Balancer. With a Strobe Light you never need to use reflective tape, clean, scrap, or sand the shaft, carry cleaning supplies (or stop by a fast food restaurant to “borrow” cleaning towels), fight to get the photo-tach or laser-tach sensor mounted and properly adjusted, and you don’t need to worry about the expensive laser or photo tach falling into the moving shaft.
With a Strobe Light Vibration Analyzer you can walk right up to the machinery and start making measurement without first shutting the machine down, it saves time, it is safer, and typical balance results are superior to the processed answers from a software-based analyzer.
Tip provided by Mark Slebodnik
President
Balmac Inc.
Plain City OH
October 02, 2008
Spectrum Visual Lubrication Management System
Colored identifiers can be assigned to lubricants allowing for a tagging system to be deployed throughout the lubricant chain.
From the point of storage to the point of application, the operator will know which designated lubricant is used at each specific lubrication point.
Find out more about Spectrum Visual Lubrication Management System
October 02, 2008
Motor Testing Tip
Effects of Voltage Unbalance on Motor Performance
Unbalanced voltages applied to a three-phase AC Induction motor will result in unbalanced circulating currents flowing in the stator windings. A general rule of thumb is that for every 1% voltage imbalance, a 7% current imbalance is expected. Circulating, or negative sequence current, can significantly increase the current demand for the same load, overheating the insulation system. The HP rating of the motor should be reduced per NEMA MG-1 to prevent overheating.
Tip provided by PdMA MCE Division
Tel: 813-621-6463
http://www.pdma.com
Discuss this tip on the Motor Testing Discussion Board at MaintenanceForums.com
October 02, 2008
Infrared Tip Feedback
As a 13 year level III I am not sure I agree with the September 18 Infrared tip at all.
Original Tip:
http://maintenancetalk.com/blog.php/tipsblog/infrared_inspection_tip5/
Emissivity and delta T is absolutely essential. Field settings are important but there are only two that cannot be adjusted in the software, focus and perspective. Depending on the type of instrument used (long wave/short wave) determines the other parameter adjustments.
Most units I have been used have paint somewhere around .85-.9 and depending on the temperature of the surface, the emissivity also changes. Shiny copper connections can be under .3 – a situation where the temperature could read from 100 at .1 to nearly 400 at .3. I trust you see my point.
Field testing of E is essential to reliable infrared thermography.
Thanks for the good work you do.
Regards.
Randy Springer
Pepper Maintenance Systems
Discuss this tip on the Infrared Discussion Board at MaintenanceForums.com
September 25, 2008
Are you attending IMC-2008?
IMC-2008 23rd International Maintenance Conference is held December 8-11 in Bonita Springs Florida.
Each year reliability leaders from over 36 countries participate in one of the best events for reliability guidance and new ideas to transform your maintenance performance.
Register now to save on conference fees, hotels and airfare.
Find out more about IMC-2008 23rd International Maintenance Conference
September 25, 2008
Vibration Analysis Tip
When checking for a suspect resonance on a fan that could not be shut down I used a strobe fired from a tunable filter set to the suspect frequency.
Unfortunately I could not find a reference point (e.g. a key way or mark on the shaft) so I coated an foam ear plug with twink (white marker) and inserted it into a short length of plastic pipe and using it like a blow gun aimed it at the shaft .
My aim was good so this left a white mark that was quite clear using the strobe. By moving the accelerometer attached to the filter around the skid I was able to see a definite 180 degree change in the position of the mark left by the ear plug when it hit the shaft.
This confirmed the suspect resonance when I also plotted out the amplitudes along the skid.
Reader tip provided by Ian McNab
Work Preparation Engineer
Transfield Worley
Eltham Taranaki
New Zealand
Good shot Ian! Thanks for the tip. Your stainless steel, diamond plate Reliabilityweb.com coffee mug is on the way.
Join the PdM Discussion at Maintenance.org
September 25, 2008
Every Reliability Program Needs a Roadmap
Whether you’re starting from scratch or renewing a commitment to the reliability journey, MRG’s Reliability Roadmap approach is the key to unlocking the benefits of a new or underachieving program.
Find out more about MRG’s Reliability Roadmap
September 25, 2008
Maintenance Tip
Not all failures of machinery that have circulating lubrication systems are trendable.
Some events occur due to abuse or environmental factors that you just can’t see coming with the best of lubricant analysis or vibration analysis. Or the case may be that you can’t economically see them coming. Payback after all is a prime consideration in the application of any PdM strategy.
Given a choice of having a piece of equipment come crashing down after it has “made metal” in the oil until the next sampling interval or having an instant alert when it starts making metal, I will always take the later choice. You at least maintain some control of the shutdown and minimize collateral damage.
This is particularly applicable to mobile equipment. But works equally well on large gearboxes and hydraulic systems. Do you want the operator to have a warning of possible impending failure or should the first warning come when the oil pressure light comes on followed shortly by seizure? A chipped gear tooth is bad, a ruined crankshaft and collateral damage is very, very bad.
In many systems it has been the practice to install magnetic drain plugs to trap particles and to allow examination. But that allows only infrequent warning of impending problems. Also for years in the higher end hydraulic systems it has been a (little used) option to install magnets in the return or case drain lines that can be removed and examined with the unit in service. This obviously allows more frequent inspection, but is still limited to some time based inspection interval.
An often overlooked and surprisingly inexpensive method for real time failure detection is the simple magnetic chip detector. These were first used extensively in helicopter gear boxes during the 60s. Even a few minutes warning that a gear box was “making metal” could be a life saver back then. A chip detector slightly resembles in size and configuration a spark plug in that it has an electrical gap in the end of it and electric leads to it. Add a magnet to a spark plug and insert it into the oil stream and it is now a chip detector.
When the magnet attracts enough ferrous debris (either a large chip or accumulated fines )the gap in the probe is bridged, a low voltage current flows, and a light or annunciator goes off. The operator is warned and a mechanic can be summoned. Depending on the circumstances and your procedures, the machinery can be proactively shut down until help arrives. The probe can be removed while in or out of service and the debris examined to determine what - if any - further evaluation needs to be performed.
For low pressure systems, a kit with the probe, receptacle, and a 12 or 24 volt indicator light can be purchased for under $300. For engines of mobile equipment there are even oil filters with the chip detector integrated into the housing for around $1000. This is some of the cheapest life insurance you will ever buy for some of your equipment. You can find providers on the web, or buy them out of aviation supply catalogs.
Tip provided by Sam McNair
Life Cycle Engineering
Charleston SC
Find out more about Life Cycle Engineering
September 25, 2008
Leadership Tip
Be Optimistic
Some people think that optimism is about living in a Pollyanna world where everything is nice and bad things never happen to good people. Well, nothing could be further from the truth. Optimism really is a courageous state of mind – one that comes from a person’s desire, effort, and choice to accept and make the best of difficult situations. Certainly, the road of optimism is not without its potholes. And that’s especially true from those in leadership positions.
If you serve as a leader long enough, you’ll undoubtedly come face to face with setbacks and unexpected events that have the potential to be devastating. People and situations change, and your ability to remain optimistic will surely be tested against fear of the unknown. Refusing to engage in the all-too-common “woe is me” lament takes courage.
The optimistic leader believes that defeat is a temporary setback – isolated to a given situation. He or she wants the best possible outcome and therefore concentrates on finding something positive and hopeful in what appears to be a hopeless situation. This is a leader who understands a basic principle of human nature: You usually see whatever it is you are looking for.
There is an endearing story about how optimistic people look at situations differently – seeing the potential that others fail to realize. It goes like this: Two researchers were independently dispatched to one of the world’s least developed countries by a large shoe manufacturer. Their task was to assess the business possibilities within that country.
When the first report came back to the manufacturer’s headquarters, the message read: “No market here. Nobody wears shoes!” A few days later, the second report came back from the other researcher. It read: “Great market here. Nobody wears shoes!”
Tip excerpted from Leadership Courage by David Cottrell and Eric Harvey
Find out more about Leadership Courage
September 25, 2008
Infrared Tip
Zoom lens adapters are available for some infrared camera platforms. Built-in zoom features are not always the best way to get an image that is presentable for quality report generation. This lack of image quality also makes correct defect classification less certain.
For collecting data at a distance, a zoom lens adapter should be used so that image quality and data collection is not compromised. There are a variety of infrared camera platforms be sure to select the one recommended by the IR equipment manufacturer you use.
Tip provided by Rich Epps
Allied Reliability, Inc.
Charleston SC
Find out more about Allied Reliability PdM Training
