Plant & Works Engineering
Ultrasound and the IIoT: the Future of Condition Monitoring
Published:  30 March, 2022

When a powerful and versatile technology such as Ultrasound meets the Internet of Things, new solutions arise that will take condition monitoring of assets to a whole new level. The development of ultrasonic sensors and their integration with data collection points promise to be a game changer when it comes to continuous and remote monitoring of industrial assets. PWE reports.

Airborne & structure-borne ultrasound has certainly become a major player in condition monitoring. Once considered just a leak detector, more maintenance & reliability professionals are beginning to realize all of the benefits associated with using ultrasound for condition monitoring applications.

The P-F Curve with which we have all become familiar with reflects that trend: ultrasound is considered one of the first lines of defence against unplanned downtime, being able to spot bearing failures at a very early stage. Besides, ultrasound is well known for its versatility: the technology can be applied to different domains such as leak detection, bearings condition monitoring & lubrication, steam traps & valves inspections and electrical inspections.

Traditionally, and still nowadays more commonly, ultrasound technology is used in maintenance and condition monitoring practices via handheld devices. These have been going through their own enhancements and many of them are sophisticated inspection devices and data collectors which can greatly improve any reliability program.

The Surge of Ultrasonic sensors

The ultrasonic handheld devices certainly still play an important role, but when we couple the technology with the capabilities that the internet brings us, we can create powerful monitoring solutions by using ultrasonic sensors connected to network-enabled devices. The sensors are always listening, as if an inspector was always there inspecting the asset, continuously, 24/7. They collect data from assets in the form of dB readings and send them to central devices who will process the data. This brings, of course, a huge potential for improvements on maintenance & reliability programs. We can now setup alarms, notifications, trend the condition of assets… all automatic, seamless and taking advantage of the well-known benefits of ultrasound technology.

Sensors for mechanical assets

Imagine you have an asset at your facility, let’s say a bearing. This is a critical asset that simply can’t fail. An ultrasound sensor can be permanently mounted on the bearing, continuously collecting dB readings and sending them to a data processing box. Is the dB reading abnormal? You get notified by email or SMS. You are always on top of your assets condition. Alarms can be setup according to your needs: want to know when a bearing needs lubrication? When there’s a damage on it? Want to have a sound recording of the bearing when an alarm is reached? Everything is possible since maintenance managers will be able to setup their own alarm thresholds and notifications. And make unplanned downtime a thing of the past.

Remote lubrication

When we have sensors constantly monitoring the condition of bearings, we can use the collected data also for lubrication practices. A world where lubrication is carried on remotely, based on the asset’s condition, and from any device, is now a reality. A solution such as the SmartLube from UE Systems is an example of how integrated sensors can disrupt lubrication practices. This remote lubrication assistant is watching over your bearings 24/7, notifying you when lubrication is required. When called upon, the assistant will lubricate the bearing with precision using friction as its guide and with ultrasound best practices in place to eliminate over greasing. Remote lubrication, based on condition, promises to become the new standard when it comes to predictive maintenance.

Sensors for electrical assets

The same applies to ultrasound applications requiring airborne sensors, such as electrical inspections. Place the airborne sensors next to your critical equipment, and they will be constantly listening to these assets. As soon as something abnormal is picked up by the sensors, data in the form of dB readings & sound recordings will be sent to a central processing box, which will again trigger the setup alarms and notifications. Ultrasound has proven to be an excellent technology when it comes to finding electrical faults such as corona, tracking, arcing or mechanical looseness. Coupled with online sensors, improvements in safety and inspection methods could be huge.

New Ultrasound based IIoT Solutions

There are already easy to implement solutions on the market that couple ultrasound technology with sensors and network-connected devices, allowing for truly continuous and remote monitoring. For bearings and other mechanical assets, there is for example the OnTrak, a remote IIoT bearing monitoring system using UE Systems’ Ultra-Trak 750 sensors. The system is composed of 16 sensors and a central processing box that can be connected to the network via wifi, ethernet or cellular data. Data from the sensors can be easily viewed on any laptop, tablet or phone. Real time insights and notifications can be used to constantly monitor lubrication & condition insights. Additionally, data can be integrated to cloud platforms such as Azure, AWS, Google, IBM Watson, PTC, Thingworkx, etc.

Another solution for bearing monitoring is the 4Cast, working with the RAS (Remote Access Sensors) from UE Systems. Up to 4 sensors can be connected to a 4Cast box, which then connects to the network via Ethernet to provide data insights from the bearings. Data is then sent to UE Systems DMS 6 software for trending an analysis. The great advantage of the 4Cast is its ability to also record and store sound samples from the monitored bearings – this feature, together with the ability to create instant alarms, makes the 4Cast a good solution for critical and slow speed bearings.

For electrical safety there is a solution such as the 4Site available. Similar to the 4Cast, it can record & store dB readings and sound samples from up to 4 sensors. In this case, and since we are talking about electrical inspections, these sensors are airborne. Online continuous ultrasound inspection can be performed at all voltage levels (low, medium and high) and is used to detect corona, partial discharge or tracking, arcing and mechanical vibrations (transformers).


From handheld devices to connected sensors – this is the natural progression of ultrasound technology when used in industrial environments for maintenance, condition monitoring and reliability. Such as other technologies, integration in the IoT world will become a fact, and though the current solutions are already bringing exciting advancements, there is still much to discover and explore. What we know for sure, is that with the currently available solutions, maintenance departments have very effective weapons to fight against issues such as unplanned downtime and electrical equipment failures.