This article originally appeared in IMPO's May issue.
Excessive vibration of industrial machinery is often indicative of potentially serious problems, such as unbalances, looseness, shaft misalignment and bearing or gear failure. Which can result in safety risks, equipment damage, shutdowns, unexpected downtime and lost productivity. Therefore, it is crucial for manufacturers to maintain effective maintenance programs and to become more familiar with new technology and trends associated with maintaining properly aligned machinery.
One of the first steps to avoiding vibration and misalignment problems on the factory floor is proper training. “Pinpointing the specific cause of excessive vibration can be achieved through training personnel on vibration practices and relevant standards,” says Shalvi Desai, a Marketing Communications Specialist with Wilcoxon Research Products. “Personal should also have a better understanding of process changes and the corresponding effects on vibration levels. Being aware of typical vibration levels of machines at different frequencies enables better informed analysis.” Then only through informed decisions and sound analysis can employees determine the vibration levels that are safe and effective for the machine to run at without the risk of shutting down.
The next key piece to maintaining properly aligned machinery is developing a reasonable and achievable maintenance schedule. “Big picture, we start with a lot of plants — regardless of industry — that are still in a reactive mode of maintenance, which is prone to failure, reduced production, high maintenance costs, unplanned downtime and just lots of problems overall,” explains John Bernett, an Application Specialist for Mechanical Products at Fluke. “Then a lot of companies went to preventative maintenance, but there are still a lot of problem with this because you end up setting up big problems.”
Instead of a reactive mode of maintenance — or even a preventative maintenance system — as Bernett described, it appears to be much wiser to adopt a system of predictive maintenance in regards to vibration and alignment. When using a predictive model, instead of basing maintenance on the failure of a machine or a calendar manufacturers base it off of the condition of the machine. By doing this, costly downtime can be avoided as a result of misalignment can be avoided because they are taken care of before they can create a problem.
“We don’t have production loses, we know what machines are going to fail, and we can fix them before they fail. We don’t have any downtime which cuts into our bottom line and we are also able to fix a machine before a misaligned bearing can wipe out an entire shaft or machine,” Bernett explains about predictive maintenance practices.
Choosing the appropriate monitoring equipment is also crucial in the overall development of a sound maintenance and vibration monitoring program. According to Desai, sensor selection is extremely important, however a manufacturer must be careful because there is “a wide range of sensors available for industrial environments including high temperature, waterproof, high frequency, lower power, radiation resistant and high EMI resistant.” And only a properly selected sensor will yield accurate results.
When constructing a monitoring program, cables, connectors and wiring is also extremely important — if not as important as the sensor selection. “Vibration sensors and accessories should be rugged, long-lasting and not affected from degradation over time,” says Desai.
However, it is important to consider the significant cost and investment required to not only train new experts on vibration and alignment, but also the costs of changing maintenance approaches. Because of this high upfront costs the industry is seeing the development of tools and equipment to simplify the process of vibration and alignment monitoring.
“The holy grail is having a dedicated reliability team with all kinds of people and all kinds of resources. Well, what about the rest of us what about the companies that don’t have all those resources and can’t afford a high end CMS program. The rest of us need to think about how we can do this in a simpler way,” says Bernett.
The simpler way that he is talking about is through new technology. “Technology is getting better and better and the fallout from that is that you don’t need to have a vibration expert and a laser alignment expert. With the smart tools coming on the market we have found that having several smaller smart tools can provide the same results as one analyzer and can do the very same thing,” adds Bernett. Now the entire maintenance flow can be completed with smart tools and technicians instead of having experts, which is timely as experts are becoming scarce as the baby boomers begin to retire.
Desai predicts that these advances will eventually take alignment and vibration to a place where they are simply integrated into mainstream process automation systems. “Industrial processes will simply use plug and play solutions to simultaneously monitor temperature, flow, vibration, and lubrication over a wireless or system network,” describes Desai.
The proper vibration and alignment monitoring system can be a challenge to create, and can take investments in training, new maintenance approaches and technology. However, it is an integral part to an efficient and safe facility, so it always worth the investment. It is the right time for companies of all size to create their own “holy grail” vibration and alignment system.