Two-minute tip: Using Vibration to Find Mechanical Faults
A quick guide to fault types and ways to leverage technology to screen for impending problems.
Vibration-sensing devices use accelerometers to measure changes in amplitude, frequency, or intensity of cyclical forces in rotating assets. Differentiating normal from excess vibration can help maintenance and reliability (M&R) teams find root cause prior to a problem occurring.
“We’re using vibration to diagnose machine faults,” said Bernet. “Every machine vibrates but by looking at the patterns and the amount of vibration, and comparing it to what a healthy machine looks like, we can use it as a diagnostic tool.”
Common Mechanical Faults
Misalignment: When components don’t line up precisely as noted by the manufacturer; i.e. a shaft is 3 cm to the right
Imbalance: Heavy spots in rotating equipment that can cause mechanical problems; i.e. similar to vehicular tire imbalance
Looseness: Looseness of shaft or looseness of non-rotating component looseness, i.e. loose bolts on the motor’s feet
Bearing Wear: Damage or premature deterioration to the bearings (roller, ball, or other), i.e. caused by bad or improper lubrication or grease, imbalance, or misalignment
Vibration monitoring is a well-suited method to determine equipment faults, as both mechanical and electrical problems will measurably impact rotating equipment. However, vibration monitoring is best used to determine impending mechanical faults. Even though vibration monitoring can give maintenance teams an idea of electrical faults, electrical tools are better at diagnosing power-related issues.
IIoT-enabled monitoring sensors and tools can help M&R teams find excess vibration early in the “Potential Failure” Curve. Vibration screening takes seconds and quickly indicates whether machine rotation is within normal parameters. Vibration analysis is a much more in-depth diagnosis of issues and takes longer to obtain results.
“We can’t spend time analyzing healthy machines,” said Bernet. “Let’s screen out with simple tools and eliminate the 80% of machines that are healthy.”
From there, teams can perform complex vibration analysis on the other 20% of machines to determine precisely what is wrong and how to fix the problem. Even within that section of unhealthy machines, vibration screening can help teams prioritize repairs based on current status. M&R professionals can make repairs to critical assets while keeping tabs on other unhealthy equipment that might not be as close to a failure.
About the Author
Alex DeselleProduct Specialist, Fluke Corporation
As a Product Specialist for Fluke Corporation, Alex Desselle focuses on Condition Monitoring software and product lines. He has 30 years of industry experience as a Field Engineer working across Oil & Gas and Manufacturing business verticals. He has held various positions as Lead Field Engineer, Project Manager, and SME/Product Specialist