Originally published in 2009. Updated March 2021
An ultrasonic detection device is an excellent tool as a power plant’s first line of defense in predictive or preventative maintenance. With the CTRL UL101 ultrasound listening devices, technicians can quickly locate problems in a wide range of components, equipment, and systems, enabling them to make informed decisions as to what further actions are needed to solve the problems.
Ultrasound vs Vibration Analysis and Thermography
Ultrasonic technology’s leak detection capabilities are not found in vibration analysis or infrared, yet its use in conjunction with these more widely used predictive maintenance technology is complementary. In many power plants, technicians use ultrasound when they first suspect a problem — for example with bearings — then verify what they have heard with portable vibration analysis. Likewise, ultrasonic technology can help to confirm if a bearing or gear problem exists where there is an early change in vibration analysis readings, or when thermography picks up a hot spot in a circuit breaker or switchgear. According to plant operators surveyed, ultrasonic devices are often able to better pinpoint the location of the problem in electrical equipment.
Unlike infrared or vibration analysis, acoustic ultrasonic technology is as easy to learn as it is to use. Vibration analysis can require upwards of two years of training to become proficient in its use, whereas many plant technicians can learn the basics of the UL101 in as little as an hour, and become proficient in its use through normal operation in a few short days to a week. Combined with CTRL’s recently launched CloudCTRL Learning Platform, the learning curve is even smaller and the ultrasound integration faster. Our UL101 Quick-Start Training uses an adaptive learning platform, AI, and machine learning to help users retain information longer.
Ultrasonic technology is also flexible and allows the technician to gather information rapidly. In power plants, ultrasound technology is unique in its ability to detect and pinpoint leaks in air and steam systems, condensers, boiler tubes, and water walls — something infrared and vibration analysis cannot do. This translates directly into improved system efficiency, as it allows the technician to take corrective action to prevent reduced pressure, to avoid adverse impact on the effectiveness of all systems that rely on maintaining proper pressure for efficient operation.
Pictured above: Ultrasound lubrication monitoring can detect issues long before vibration analysis or infrared.
Case Example: Condenser Tube Leaks and Bearings
A specific example of ultrasound’s ability is in pinpointing condenser tube leaks. Differences in the tubes are easy to discern if air is escaping. Leaks are easily pinpointed, so the problem can be resolved (tubes cut and capped to stop the leak). When talking about how much faster condenser tube leaks can be found and repaired, one user remarked, “the time savings have been incredible with ultrasound.”
In the case of bearings, vibration analysis is often inadequate. At the point when vibration analysis is just beginning to show signs of something happening, ultrasound can only not “tell” the operator if the bearings are over or under-lubricated or out of round, ultrasound can pinpoint which bearings need immediate attention. In fact, ultrasound can often detect a bearing problem long before the problem is identified through vibration analysis or infrared — before costly damage or catastrophic failure occurs.
Determining inadequate or improper lubrication is one of ultrasonic technology’s strengths. A two-year study of ultrasound at one nuclear facility focused on its use in monitoring the condition of bearings on cooling tower fan motor bearings, which are grease lubricated. Each time a bearing was identified as bad by ultrasonic analysis, maintenance work proved that the bearing was indeed bad. With the cost of fan motors between $2,000 and $4,000 and labor costs in the same ballpark, one prevented failure paid for the cost of the UL101 device. During times of peak demand, failure of the fan motors could mean less ability to meet customers’ needs.
Ultrasonic technology is used in many coal plants to check the roller bearings on conveyor systems. Despite the length of a conveyor system easily a mile long, a technician is able to quickly check bearings. One user said, “ultrasonic technology is a much better tool than vibration analysis for these types of bearings,” while another user stated that ultrasonic technology is a “quicker method to investigate suspect bearings.”
Being able to check a wide range of components, equipment, and systems is just one reason why ultrasonic technology has an advantage over fixed systems. The UL101’s lightweight, portable, and durable features mean that unlike fixed monitoring technologies, ultrasound can be used throughout the facility. A technician can use it to check bearings, gears, valves, and other critical components in any rotating equipment in the facility quickly and easily in as little as a few seconds.
Ultrasound and Energy Savings
High energy costs have spotlighted a facility’s need to reduce wasted energy wherever possible. The Department of Energy estimates that a facility expends 15% of its energy dollars on compressed air. Just one ¼’’ compressed air leak can cost anywhere from $6,000 to $10,000 per year. Leaks you didn’t know existed can be quickly found. Considering that multiple leaks are found in any one facility, the savings realized from locating and fixing the leaks can save a facility thousands of dollars. In addition to the money wasted, one operator remarked that leaks in the compressed air system, “could bring down the plant.”
Most facilities have steam traps or steam lines, which are even more costly to operate from an energy perspective than compressed air. Equipment and systems that rely on steam to operate effectively suffer when leaks go undetected and unrepaired. Ultrasonic technology easily detects leaks in steam traps and steam lines, being called “more reliable” and a “more positive indicator than infrared”, as well as producing “great savings” through its use. One failed steam trap can cost thousands of dollars per year, but ultrasound can detect a failed trap in a few seconds.
It’s easy to see why ultrasonic technology has become a routine part of maintenance for so many power plants today. Whether used as part of a regular preventative or predictive maintenance program, or for special applications beyond the reach of other technologies, the reasons for using ultrasonic technology are clear: Portable. Durable. Easy to use. Small learning curve. And a recognized return on your investment — often in one user or within one month of use.
CTRL Systems is an international leader in manufacturing ultrasonic technology for use in power generation, distribution, and transmission. To learn how our products like the UL101 Electrical Inspector and the PowerBeam 300 can be used for your facilities, speak to one of our ultrasound experts today at +1 (877) 287-5797, or schedule a free quote or demo.