Ultrasonic detection has existed for over 25 years and is widely used throughout continuous process operations for a variety of predictive maintenance applications. Thanks to revolutionary advancements in the last several years, maintenance personnel are specifying ultrasonic detection with increased regularity for everything from acoustic vibration monitoring to leak detection and electrical problems.
Learn about the boundless applications that exist for ultrasound testing and you will realize that a complete arsenal of predictive maintenance tools must include advanced ultrasonic inspection equipment.
WHAT IS ULTRASOUND?
Ultrasound, as the name implies, is sound above the human hearing range. The audible sound that you hear is only a small part of the total spectrum of sound that actually exists. With the use of an ultrasonic detector, high frequency ultrasound is translated into the audible range where it can be heard through a headset and measured quantitatively for trending.
Ultrasonic inspection takes you into a different world of hearing, effective in the loudest of industrial environments. Ultrasonic waves are high frequency, short wave signals. They attenuate very quickly and are very directional in nature. These properties make it possible to filter out stray, confusing background noises and focus in on the specific item to be inspected. In addition, testing is best done under actual operating conditions. These properties make them ideal for use in high ambient noise, production critical environments.
HOW IS ULTRASOUND CREATED?
High levels of ultrasound are created by:
WHERE IS ULTRASOUND USED?
Compressed air leaks add to everyday operating costs and affect the life of your compressor. Estimates given by the US Department of Energy show that in plants with no routine leakage programs, roughly 30% of compressed air is being lost. Fewer leaks mean less demand on your compressor motors and a reduction in electricity consumption.
Another proven contributor to energy loss is faulty steam traps. Steam traps can fail for a variety of reasons allowing steam to escape. Since the system is closed, it is not possible to know if the trap is operating correctly without the proper tools. Ultrasound is the preferred method for monitoring flow-noflow conditions of steam traps.
Friction generates ultrasound. As internal components in moving machinery wears, increased friction creates changes in the ultrasonic sound being generated. NASA research reveals that ultrasonic monitoring provides early warning of bearing failure. These changes in ultrasound show up before other signs like heat or vibration are detectable.
One of the largest causes of bearing failure is over lubrication. The excess stress of lubricant often breaks bearing seals or causes a buildup of heat which can create stress and deformity. Ultrasound can be used to determine the proper lubrication intervals on a 'need' instead of 'time' basis and can be used on high as well as low speed bearings.
Electrical arcing problems give early warning and sound like the sizzling of frying bacon in the ultrasonic range and can be localized before enough heat is generated to be 'seen' with thermal imaging.
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Pressure leaks |
Vacuum leaks |
Leaking Valves |
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Hydraulics |
Pump Cavitation |
Heat Exchangers and Condensers |
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