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Best Practices In Ultrasound Assisted Lubrication. Adrian Messer UE Systems, Inc. adrianm@uesystems.com. Lubrication Related Failures. The majority of premature bearing failures are lubrication related Under lubricated Over lubricated Wrong lubricant Lubricant contamination.
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Best Practices In Ultrasound Assisted Lubrication Adrian Messer UE Systems, Inc. adrianm@uesystems.com
Lubrication Related Failures • The majority of premature bearing failures are lubrication related • Under lubricated • Over lubricated • Wrong lubricant • Lubricant contamination Source: "Pump Users Handbook: Life Extension” 2011 by Heinz Bloch
Lubrication Related Failures? “as many as 60 to 80 percent of all bearing failures (catastrophic, functional and premature) are lubrication-related, whether it's poor lubricant selection, poor application, lubricant contamination or lubricant degradation1.” 1 Mark Barnes, “What Exactly is a Lubrication Failure?” Machinery Lubrication, formerly of Noria Corporation
Ultrasound Assisted Lubrication In this presentation we will discuss: • What is Ultrasound Assisted Lubrication • Ultrasound Technology and Instruments • The advantages of Ultrasound • Procedures for Ultrasound Bearing Inspection and Lubrication
Ultrasound Assisted Lubrication • Traditional lubrication programs include preventive procedures that include time-based lubrication. • Lubrication is performed at set timed intervals with a specified amount of grease applied
Ultrasound Assisted Lubrication • The issue with time-based lubrication is, what if the bearing being lubricated has a sufficient amount of grease already and therefore DOES NOT need lubricant. This produces an inherent risk of Over-Lubrication.
Ultrasound Assisted Lubrication • Another issue is the time-interval for lubrication. Is it correct? • What if some bearings require lubricant to be applied more frequently than assumed or what if the time interval can be stretched out?
Ultrasound Assisted Lubrication • These issues do not preclude the need for standard preventive procedures such as calibrating grease guns, measures to ensure the correct lubricant is used for the correct application, etc… • The concept is to assist current lubrication procedures with the addition of ultrasound technology
What is Ultrasound Assisted Lubrication? • Adding ultrasound monitoring to standard lubrication best practices can prevent potential over lubrication of bearings which can also lead to fewer bearing failures, extend motor and bearing life as well as lead to a decrease in the amount of lubricant used This will produce: • Savings in maintenance costs, lubricant, man-hours • And improved asset availability and reliability
Infrared Start Failure Oil analysis Structure Borne Ultrasound Vibration Audible noise P P2 P1 Contact heat P3 P4 P5 Predictive Domain Fault Domain Proactive Domain P6 F LUBRICATION DOMAIN OPTIMIZING BEARING LIFE! (DMS & GREASE CADDY) EARLY WARNING OF BEARING FAILURE Max time for planning
What is Ultrasound Assisted Lubrication? • Airborne & Structure-Borne Ultrasound instruments sense friction. • Trending associated amplitude levels and changes in sound quality of a bearing provide early indication of conditions such as lack of lubrication and prevent over-lubrication
What is Ultrasound? • High frequency sounds that are above the range of human hearing • The ultrasonic range begins at 20 kHz • There are three Generic Divisions of Ultrasound: • Pulse/Echo • Power • Airborne/Structure Borne
Ultrasound Advantages • Provides Earliest Warning of Failure • Isolates Signal • Quality of Bearing • Detects Lack of Lubrication • Finds defects not found in time based lube routes
Ultrasound Advantages • Prevents Over Lubrication • Can Be Used on Slow Speed Bearings • Complements Other Technologies • Thermography • Vibration Analysis • Oil Analysis
Ultrasound Applications • Bearings • Pumps (Cavitation) • Motors • Gears/Gearboxes • Valves • Steam Traps • Leak detection • Electrical Inspection
How Ultrasound Instruments Work • Instruments based on airborne & structure borne ultrasound sense high frequency emissions produced by turbulence (from leaks), friction (in mechanical equipment) and ionization (generated by electrical emissions) • They translate these sounds down into the audible range through an electronic process called “Heterodyning” • Sound is measured by a decibel level that is indicated onboard the instrument
How Ultrasound Instruments Work • The heterodyning feature enables users to hear the translated signals in headphones, record sound samples and analyze sounds through spectral analysis software. • Data from test results can also be viewed on a display panel
Sounds Are Received Two Ways: -Through a contact module or wave guide -Through a scanning module
Instruments used for Lubrication Programs • Digital instruments: • Set baselines • Log data • Record sound sample • Analyze Sounds • Download all data to Data Management Software dB Level
Digital Instruments • Data Logging • Sound Recording • Data Management Software • Improved Record Keeping, Recording, Reporting • Spectral Analysis
Analog Instruments Listen to heterodyned ultrasounds View intensity levels only (not dB)
Analog Instruments Intensity Display
Procedure • Use the digital instrument • Collect data • Record sounds • Download to Data Management Software
Procedure • Review data • Create Trend Charts • Analyze Sound Samples of deviations
Analyze Sounds For Differences Baseline Sound Sound Deviation
Action Levels • 8 dB Lubrication • 12 dB Minor Damage-Microscopic Faults • 16 dB Damage-Visual Faults • 35+ dB Catastrophic Failure Imminent Severe Failure dB
Procedure • After review of data • Sect bearings in need of action for either: • Repair • Lubrication
Procedure • Assign analog ultrasound instrument to lube technicians • Instruct them to add enough lubricant to cause a drop in sound levels while observing the LED intensity indication • Add lubrication – Meter intensity levels drop • Use caution - Lubricate A little at atime
Procedure • If bearing needs grease, dB will decrease as lubricant is applied • If bearing is already over lubricated, dB will start to increase while applying lubricant • If there is no change in dB, further action should be taken to see why there was no change, or bearing is in a failure mode that lubrication is not the solution
Examples of Over Lubrication The biggest problem we find in bearings is that they are over greased. The maintenance man doing the greasing usually does not know how much grease is put into the bearing. In the past we just pumped a few strokes into the bearing and then said well that ought to do it. Usually that was too much grease and these pictures show the results of that style of greasing.
Examples of Over Lubrication In the case of this motor there was no attention paid to how much grease was being put into the bearing. This motor actually had shielded bearings in it and there was no grease getting into the bearing, so it never cooled down and never got any quieter so they just continued to grease it. After a point, there was so much grease in it that the motor started to heat up. What did they do then? THEY GREASED IT SOME MORE.
Ultrasound Assisted Lubrication Best Practices • Prioritize equipment based on an asset criticality list • Likelihood of a failure, runtime, cost to repair, consequences of a failure • Set up routes to collect ultrasound data including recording sound files • Once initial readings have been taken, a baseline is set
Ultrasound Assisted Lubrication Best Practices • Once a baseline has been established, alarm levels are set • Data (dB) only is collected until an alarm has been reached • Ultrasound is used to lubricate points that are currently in a “low alarm” condition • Grease is applied until the dB returns to the normal level
Ultrasound Assisted Lubrication Best Practices • For more critical assets, a follow up reading should be taken to ensure that the dB did not rise again after lubrication, or use a complementary technology for a “second opinion” • PM’s may need to be adjusted to reflect the use of ultrasound while greasing, frequency, type of lubricant, etc…
Benefits of Ultrasound Assisted Lubrication • Identifies bearings in need of lubrication • Prevents over lubrication of bearings • Reduces the amount of grease kept in inventory • Reduces incidents of bearing failure • Reduced labor lubricating bearings • More effective PM’s • Improves asset availability
Questions? Adrian Messer adrianm@uesystems.com (914)282-3504