Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/359954
6 | July - August 2014 | www.machinerylubrication.com JeremY wrIght | NorIA CorPorAtIoN o i l A n a l y s i s From the FIeld Have you ever seen a mechanic open a toolbox that only had a single wrench or a carpenter with a tool chest containing just one type of saw? For these individuals to be considered true professionals, they must amass giant collections of tools so they can properly complete a task or job. In a similar way, a predictive maintenance (PdM) professional's inspection "toolbox" should comprise a host of options, including infrared thermography, electric motor circuit analysis, vibration, oil analysis and ultrasonic/sonic analysis, as well as visual, tactile and acoustic (sensory) inspections. Field experience has demonstrated that by appropriately combining and relating the results of different inspection options, these professionals can create a synergistic solution. This approach is much more thorough than one based on only one test or on several non-integrated inspection methods. This article will explore how these technologies and tools can work together to achieve far more than when implemented independently. infrared Thermography Analysis Heat is often a symptom of eminent machine failure or malfunc- tion. A non-contact infrared imager can be used to quickly obtain a multipoint temperature profile that can easily be assessed. This inspection can be performed with little to no disruption to the facility's operations. When utilized as a screening tool as part of a daily or weekly inspection, it can frequently be the first method used to witness a pending component failure. Sonic/Ultrasonic Analysis These instruments generally sense sounds in the 20- to 100-kilo- hertz range and convert them to either auditory or visual signals that can be heard/seen by a technician. These high frequencies are the exact frequencies generated by worn and underlubricated bear- ings, faulty electrical equipment, leaky valves, etc. This can also be a great way to detect an impending machine failure before it becomes catastrophic. Motor Current Analysis In the realm of electric motors, the current signature can be measured and recorded. In its infancy, it was primarily employed to detect rotor bar problems, but today with demodulated spectrums, the technology can be used to identify issues with belts and couplings through trending and baselining. Vibration Analysis In its simplest form, vibration analysis is a measurement of displacement over time. By measuring displacement, velocity or acceleration, you can get insight into bearing failures, imbalance, misalignment, wear, looseness, etc. Oil Analysis The lubricant is considered the lifeblood of the equipment. Much like a doctor assesses your health through blood analysis, the same can be done for machine health. Oil analysis can be broken down into three main categories: lubricant health, machine health how to leVerAge mUltIPle Predictive maintenance technologies The Human Senses: A valuable Condition Monitoring Technique EffEctivEly using somE condition moni- toring tools, likE vibr ation or oil analysis, requires a considerable amount of training. sensory inspection, on the other hand, can be performed by non-maintenance personnel such as operators. this can be an advantage when the maintenance staff is occupied with reactive maintenance tasks. something as simple as detecting an oil leak or a gearbox that sounds weird could and often does lead to the prevention of a catastrophic failure, avoiding tens of thousands of dollars in losses. therefore, the value of utilizing your senses should not be underestimated or overlooked.