In the past three years falling prices and a desire for early-detection capability have led to a large level of investment in vibration monitoring and thermal cameras – two of the major techniques in what is collectively known as condition monitoring.
As the majority of businesses who sell the equipment offer other services, it’s difficult to give a figure for the industry’s size. But to give an idea of the increased uptake, leading condition monitoring supplier for the rail industry, Tracsis saw has seen its share price more than double since 2013.
Condition monitoring is a predictive maintenance technique that can spot problems with machinery before they bring your operation grinding to a halt. This has the dual benefit of prolonging machines’ lifespan and reducing downtime due to machine failures.
As the names suggest, in simple terms thermal cameras use heat mapping to detect problems and vibration monitoring collects data on parts that may not be performing as they should due to being misaligned or worn.
But the techniques are not as simplistic as some would have you believe. Ian Pledger, field service engineer at Schaeffler, explains the difference between common perception and the reality.
“People refuse to see that thermography and vibration monitoring are complicated technologies. They just don’t want to believe that,” he says. “For example, they believe that a thermal imaging camera reads temperature. It doesn’t, it reads calibrated infrared radiation. People also believe vibration is a number like degrees Celsius. Again it’s not, it’s a wave form generated by how the machine is performing.”
The potential gains appear significant. One model which is to be unveiled at 2016’s Hannover Fair 2016 is ABB’s internet-enabled smart sensor. The device promises to reduce motor downtime by up 70%, extend lifetime by as much as 30% and lower energy use by up to 10% through a combination of vibration, temperature and sound monitoring. The actual figures for in-the-field testing are difficult to pin down, but most agree that, when applied properly, the techniques do add value.
David Manning-Ohren, condition monitoring manager, ERIKS, gives the example of vibration monitoring equipment collecting trending data. This essentially gives users reactive read-outs to forecast future issues.
“Trending is basic but it’s incredibly powerful,” he says. “To give an analogy, it’s like your printer saying when you’re about to run out of paper but for your large industrial machines. It can really stop you running into some very serious problems.”
Back to basics
But not all plant engineers are getting the most out of condition monitoring, Manning-Ohren believes. He believes their eagerness to bring these gains to the factory floor, some are forgetting to put the basics in place first.
He adds that, on the most fundamental level, some who are buying the equipment are not even sure exactly how to use it.
“There’s a great lack of understanding on the part of some people who want to start condition monitoring. People don’t necessarily realise how involved the implementation of this technology can be,” he says. “There’s a general thought that ‘we’ve bought a condition monitoring device. That’s us done, we’re condition monitoring’. But that’s just the part of it.
“People often miss the preparation behind what machines are going to be monitored and even what technique is going to be used. So there are a whole lot of decisions that need to be made before signing the cheque for the equipment.”
That preparation involves both understanding condition monitoring’s place in a wider strategy and taking practical measures, says Duncan Maxwell, reliability manager at PEME.
“There will always be a need for a directed maintenance task, someone who walks round and looks at the machines on a daily basis. Once you’ve worked out how condition monitoring fits into that wider maintenance programme, then you can move forward, he explains. “Then once that’s in place, it’s a case of making sure things like your machine lubrication if correct, you’ve got a competent and all-round preventative maintenance programme and things like service contracts are in place.”
Comprehension of exactly which of your machines add the most value, which are the most prone to breaking down and which could bring production to a standstill, is crucial, according to Manning-Ohren. He recommends drawing up a “criticality list” based on this information to avoid buying expensive equipment where it isn’t needed. But he is quick to point out that, even though this in itself seems a big undertaking, it’s not from the end of the process.
“Doing the correct preparation and buying the gear is only the start of it,” he confirms. “We’ve found in recent years that if somebody who is nominated to do the job is also doing other things, quite often those other things take priority over condition monitoring. So sometimes you find that in a few months’ time the equipment is still in the cupboard, the battery’s gone flat and it’s end of story,” he adds.
The value equation
The good news is the initial outlay for condition monitoring equipment, especially thermography, need not be as great as it always was.
A product like the new-to-market FLIR AX8 Thermal Imaging Camera can now be bought for about £700 in the UK. However, this doesn’t mean the more expensive technology has been usurped, according to John Reynolds, area sales manager, FLIR.
“It’s not a question of the new, cheaper products replacing, but complementing the bigger ticket items,” he suggests. “One gives a snapshot and the other is more of a deep dive. It’s like the difference between having a low-end digital camera, which is very much point and click, and a much more complex piece of kit that requires calibration and skill to use in an effective way.”
This view is reinforced by Maxwell from PEME. “You can pick up thermal cameras for few hundred pounds now. And on the other hand our most expensive product costs around £30,000,” he says. “The difference in price really signifies the difference between a high-end analytical tool and at the lower end what you’d call a tradesman’s tool.
“For example, with the tradesman’s tool you can tell if a particular motor is running hot. And you can establish whether it’s drive end or non-drive end. At that point you can then bring in the specialist with the analytical equipment to work out why it’s running hot. So it’s very much about linking the two to achieve the end result.”
This distinction between the analytical equipment and toolbox-ready products also extends into the aforementioned training issues, Maxwell adds.
“If you’re spending seven or eight grand on the camera, you’ll most-likely buy the training course to go with it. With the cheaper products, there’s an understanding that any training will be relevant to that kind of equipment. The introduction courses are necessary so people understand both the limit of themselves and the equipment. And there’ll always be that next level of training required for the deeper analytical systems,” he says.
No magic bullet
In any walk of life, being realistic in your aims is key to getting the best results. And condition monitoring is no different, according to Ian Pledger. He warns that plant engineers looking for a “magic bullet” will be disappointed, and everyone using the equipment needs to be aware of the challenges around it.
This level of denial can lead to equipment being used incorrectly and in many cases “do much more harm than good”, he warns.
“People want to use the equipment as a one size fits all solution,” he says. “In some instances the compromises are okay and in some instances they’re not. Some people think ‘because it works on a fan motor, I can apply it to a gearbox.’ If they actually just thought about that statement for a moment they would realise that those machines are totally different. However, you still see people using the same technology and taking the same data from both.”
One thing that is clear is that, to get maximum value from condition monitoring equipment, a lot of work needs to be done. But all the hard work will be worth it if you know what your end goal is and are realistic about the time and resource it will take to achieve it. Keep that in mind, understand the level of equipment you need to your particular needs, and it is possible to add real value using condition monitoring.
