Reducing maintenance time: implementing online monitoring and remote lubrication with ultrasound

CHRISTOPHER HALLUM began his career working in the British Royal Air Force as a ground electronics engineer on radar systems and communications systems. This involved many maintenance tasks and running maintenance teams. He went on to work in the rail industry, principally as an instructor, teaching people the principles behind electrical systems and electronics before coming to UE Systems Europe, as a trainer, teaching people the wonders of ultrasound.

Today, after six years with the company, Chris is now operations manager for Northern Europe at UE Systems Europe. But his expertise in teaching and instruction are evident when he presents a webinar. That’s the beauty of the free IP&E webinars: you get to learn from renowned experts in their fields, and the interactive nature of the webinars means you get to ask questions. And it’s less embarrassing than asking a question at an in-person event because the questions are typed into a dialogue box and asked by the moderator, so there’s nothing to fear if public speaking isn’t your forte. 

Attendees of this webinar, which was held in February (but is still available to watch-again from our website), came from very different industries, with very different roles within their organisations, from students and apprentices right up to CEOs. Probably of less interest to the latter group – but another great thing about IP&E webinars – is that attending them can count towards your CPD (continuing professional development) and many delegates who listened to the one-hour event received certificates by email after the event.

Ultrasound, the name of the game

Ultrasound was the name of the game for this seminar. Chris gave his insight on how maintenance engineers should conduct their lubrication and monitoring programmes on the assets around their sites: reducing maintenance time by implementing online monitoring, and remote lubrication, using ultrasound. The webinar covered a raft of different topics within the areas of lubrication and bearing monitoring, and all condition monitoring technologies. Chris may have progressed through the ranks at UE Systems but, as he said: “My aim has always been to be there to help and support users with implementing ultrasound to help improve their reliability and uptime on their plants.”

UE Systems is a USA-based company originally founded back in the early 1970s. It is a manufacturer of airborne and structure-borne ultrasound instruments, traditionally focusing on handheld equipment. The company also develops software and sensors, and provides training and support to its users. In recent years, the company has expanded into the field of online systems, providing online solutions to its users. Its main headquarters are in Elmsford, New York. But it regional headquarters on all continents across the globe. 

“There's nothing better than seeing engineers on site, getting wins and gains that help them in their day-to-day life and running of their sites,” said Chris before going into the basics of ultrasound. In this presentation Chris was talking specifically about the way ultrasound is generated by friction. There are two ways that ultrasound is generated: friction and turbulence. Ultrasound has many applications, and is a versatile technology that can be used for many different functions: leak detection, vacuum inspections, electrical inspections, valves and steam traps. But in this webinar Chris was looking specifically at how ultrasound is used on bearings in rotating equipment. So, in this instance, we're looking at ultrasound generated by friction: sensors monitor the high frequency emissions, which then detect subtle changes in amplitude depending on what is causing the level of increased friction.

Tracing the D-I-P-F curve

“A lot of people involved in the reliability world in the maintenance and engineering world will be familiar with the D-I-P-F curve, looking at overall reliability, maintainability and availability of our assets. Now, reliability is built into an asset from the start, why we use condition monitoring or predictive monitoring technologies is to help us identify early warning signs of impending problems. And then by identifying those problems and performing things like root cause analysis, we can feed back to the designers of those assets that can then hopefully change the design to help remove those potential failure modes, hence increasing the reliability,” said Chris

Ultrasound is one of the early detectors of a change in condition. One of the key indicators of a change in the condition of an asset is ultrasonic high frequency emissions, the sounds that are beyond the spectrum of human hearing.  Chris explained: “We can also use ultrasound proactively before there is a problem present to help us with our lubrication, because lubrication practices are all about improving the level of friction.”

Over 80% of premature bearing failures can be traced back to poor lubrication, either too much grease or not enough. Over-lubrication is as big a problem as under-lubrication, as Chris said: “The amount of times I've asked somebody on a site, ‘how do you know when you've put enough grease in?’, and they still tell me to this day, ‘oh, when I see grease coming out of the sides, I know I've put enough in’. Well, well done, we've just broken the seal, and there's more damage going to be caused by that. “

Ultrasound can also help detect unsuitable lubrication – the wrong type of grease – applied due to human error. One of the biggest issues when it comes to lubrication-related failures is contamination, getting in the actual bearing itself within that lubricant, causing irreversible damage to the bearing.

The top four lubrication failure modes

So first of all, let's look at time-based manual lubrication approach. This sort of approach is the most commonly used approach to lubrication. The departments will set the frequency of application and set the required amounts of lubrication, as specified by the OEM guidelines. This is an approach that is littered with pitfalls, in Chris’s opinion. Slight changes in the way the machinery is used will change the amount of lubrication required. Human error can creep in. And with hundreds or thousands of bearings on a site there are hundreds of thousands of ways in which human error can creep in.

“Have we ensured that the end of our grease gun is actually clean as well?” asked Chris. “The amount of times I've watched people going around with grease guns, just placing it onto the bearings, onto the lubrication point, with no cleaning of any points. And if we get some contamination into that, then it's just going to turn that grease into a very corrosive material.“

Automatic lubricators are a good way of providing continuous lubrication to our bearings. It helps us with removing the risk of contamination because they are permanently mounted to the machinery. They can also be remotely activated. But even with automation, some similar questions will still come to light: is the right amount of grease being dispensed every time? Is the asset actually running while the lubricator is dispensing that grease? How much grease is remaining in that automatic lubricator? And does the bearing require grease at that time?

“Whether it's enough or not enough, I've been to many sites before now where I've walked along and seen many auto lubricators in place that are either empty or the asset hasn't been running and greas is just pouring out of the sides,” said Chris, “so we need to have automatic lubricators in the right place for the right application. Automatic lubrication is often still a time-based lubrication practice.”

Next there are conditioned based maintenance programmes. where we apply our lubrication in intervals dictated by the results of predictive maintenance inspections. We can use ultrasound devices to take baseline friction information from our bearings. From that baseline level of friction, we can set alarms, giving us an indication when lubrication is required. 

Once we get those inspections in place – repetitive, regular information and data – we can then utilise the results of those inspections. And look at lubricating only those bearings that triggered an alarm. “So we're now doing an on-condition based lubrication programme, instead of just doing it because the PM says so and it's been so many months since it was lastly lubricated,” said Chris. “So this can help us with avoiding over- and under-lubrication, because the lubrication technician can take the device with them to the greasing point, apply a ultrasound sensor onto the bearing housing, and they can then listen and monitor the display to look at the level of friction.

“If you have a baseline, for example, on a bearing that’s saying 20 decibels, and three months later you come back it's still registering 20 decibels, a time based PM might tell you to grease it again. But now you have that extra data with regards to ultrasound, would you really want to apply more grease at that time if it hasn't changed in its condition?”

The fourth mode: online maintenance

There are still human factors, and their associated risks, with a condition-based maintenance regime. So Chris suggests a fourth way: online condition monitoring of rotating assets., a system through which we can monitor the bearing condition, set baselines, set alarm levels, configure notification systems, and have access to a dashboard for the condition from any device. 

This is where Chris brought attention to UE Systems’ OnTrak SmartLube system which gives maintenance managers the ability to centralise operations using Modbus connectivity into SCADA systems, into OSI Pi, into PLC systems and with the ability to send it to cloud-based software. The OnTrak SmartLube system comprises: OnTrak, an IIoT bearing monitoring system designed to proactively identify lubrication needs and warn users about bearing issues at the earliest point possible; SmartLube, a remote lubrication system, and UE Insights Cloud, which lets you view machine and sensor data on the customisable visualisation dashboard via any web browser on any device – phone, tablet, or laptop. This can be configured to send alerts on bearing condition through email or text messages based on the criteria you select.

Watch for more information

The webinar went into far more detail than we can possibly fit into a magazine article and, of course, features not just Christopher Hallum’s presentation but also the audience’s questions and his answers, bringing in even more detail and clarity. The webinar can be watched, in its entirety, by visiting our website at ipesearch.co.uk, clicking on “Webinars” from the menu bar, scrolling down to “Reducing Maintenance Time: Implementing Online Monitoring & Remote Lubrication with Ultrasound” and clicking “Watch For Free”.

Chris Hallum is operations manager, Northern Europe, for UE Systems Europe

For more information:
www.uesystems.com