Vibration Sensors Enable Smarter Predictive Maintenance
Modern manufacturing equipment increases the efficiency of operations, but when unexpected breakdowns occur, it can cost thousands of dollars per hour in lost productivity, repair and labor. Fortunately, remote vibration sensors can be used to develop a smart, predictive maintenance strategy that minimizes equipment failure and expensive downtime.
By recording and studying the vibrational patterns of critical equipment, it is possible to detect abnormalities and identify changes in an asset’s operational behavior so issues can be addressed before failure.
The blog explains the how-tos and benefits of remote vibration monitoring, as well as the role vibration sensors play, so you can devise a predictive maintenance strategy that reduces unplanned downtime and increases profitability.
What Does a Vibration Sensor Do?
Most machines vibrate during normal operation, but excessive vibration can cause wear and tear, shorten the lifespan of machinery and create imbalances that damage components in industrial equipment. Abnormal vibration patterns also indicate possible mechanical issues in equipment.
Implementing a vibration monitoring program as part of an overall maintenance strategy makes it possible to detect changes in vibration as they occur so potential problems can be recognized, diagnosed and repaired before breakdown.
At the heart of a vibration monitoring program is a vibration sensor, which measures and records the frequency and amplitude of vibrations in industrial equipment. Collected data provides vital information about the health of your machinery.
Monitoring vibrations helps manufacturers:
- Detect bearing failure.
- Identify misalignment.
- Spot imbalance.
- Reveal looseness or wear and tear.
This insight supports predictive maintenance, allowing repairs to be scheduled when needed, minimizing downtime and costly repairs.
The Benefits of Vibration Monitoring
A vibration monitoring program should be included in all maintenance strategies, including condition-based, predictive and prescriptive maintenance programs, as it offers a variety of time- and money-saving benefits, including:
Cost Savings: Vibration monitoring identifies potential equipment failures before they occur, minimizing unplanned downtime and repairs, which can cost thousands of dollars per hour and wreak havoc on production schedules.
Improved Uptime: Vibration monitoring allows early detection of machinery issues before they negatively impact performance and operations. Monitored equipment runs with higher levels of efficiency, reliability and uptime.
Identifying Correct Maintenance Intervals: Rather than performing maintenance tasks on a calendar-based schedule, vibration monitoring allows maintenance activities to be performed as needed. This extends time between maintenance intervals, reduces unnecessary maintenance and labor costs and maximizes machine availability.
Reduced Energy Costs: Equipment that suffers wear and tear, imbalances and misalignment does not run efficiently. By identifying and correcting vibration-related issues, machines run optimally and consume less energy.
Improved Asset Management: The information collected from a vibration monitoring program provides a better understanding of the facility’s assets by providing insight into equipment health and lifespan, allowing informed decisions about whether to repair or replace assets.
How Do You Measure Vibration?
Vibration monitoring is a five-step process that includes:
| 1. Collecting vibration data | Vibration data can be collected using hand-held devices, wired sensors or remote (wireless) sensors. Using wired or wireless sensors makes the job less time consuming and reduces the chances of introducing errors into the data because technicians do not need to walk from machine to machine taking readings, nor do they need to record data manually. Remote vibration sensors provide more benefits than wired sensors as they do not require expensive wiring and can be mounted on machinery that is difficult to reach or located remotely. |
| 2. Creating a baseline | To create a baseline, vibration data should be collected when machines are running optimally. Having a baseline measurement for healthy equipment allows comparison with data that is collected later to determine when there is a change in vibrational patterns under the same running conditions to identify potential issues. |
| 3. Storing vibration data | Using remote sensors as part of an online monitoring system makes storing vibration data easier. The creation of historical data sets makes comparing baseline and future data sets possible. |
| 4. Analyzing vibration data | Analyzing vibration data is key to the success of the vibration monitoring program. As data is collected, it should be compared to the baseline vibration levels so that abnormalities, anomalies and potential failures can be identified with adequate time to schedule repairs and order replacement parts. |
| 5. Making informed decisions | Using the data in this way allows you to make informed decisions based on reliable data. This means that when an abnormal running condition or a potential failure is detected, work orders can be issued and prioritized, parts may be ordered in advance and repairs can be conducted to prevent lengthy, unplanned and expensive downtime, potentially saving thousands of dollars in lost productivity and costly failures. Informed decision making gives maintenance managers confidence when creating maintenance schedules and budgets, while the earned reliability gives production managers assurance that they will meet production goals. |
What Are the Different Types of Vibration Sensors?
Vibration sensors are a broad category of technologies designed for different applications and budgets. Sensor selection depends upon factors such as frequency range, application environment and cost.
Commonly used vibration sensors include:
- Accelerometers: The most common vibration sensor measures acceleration, which is often integrated to calculate velocity or displacement. They are best for high-frequency fault detection (like bearing faults).
- Velocity Sensors (Velometers): These measure the speed of vibration and are used for mid-frequency measurements, which reveal issues such as imbalances and misalignment.
- Proximity Probes (Displacement Sensors): These non-contact sensors measure the distance between the probe and a rotating shaft. They are crucial for monitoring shaft position and detecting faults in high-speed rotating machinery like turbines and large compressors.
- Remote/Wireless Sensors: These are accelerometers with integrated wireless communication, power and, often, data logging/processing capabilities. They are the ideal choice for proactive, continuous monitoring without costly wiring, as championed by JHFOSTER.
What Are the Three Types of Vibration?
Three types of vibration are analyzed in vibration monitoring programs and each is meant to diagnose a specific equipment issue, as follows:
Displacement: This measures the total movement or distance that a vibrating object travels from its rest position. It is most useful for diagnosing slow-speed machinery and monitoring large movements.
Velocity: This measures the speed of the vibration or how fast the component is moving. It is used for mid-frequency analysis, which can be predictive of common machine faults such as misalignment and imbalance. It typically correlates well with the destructive energy of vibration.
Acceleration: This measures the rate of change of velocity. It is most sensitive to high-frequency events, making it ideal for identifying early-stage faults like those in rolling element bearings and gear mesh problems.
Where to Place Vibration Sensors
Optimal sensor placement is key to collecting meaningful vibration data. Below are practical guidelines for where and how to mount vibration sensors on machine components.
General Placement Rules
Bearing Housings: The most common and effective location for sensor placement, as most critical mechanical faults (imbalance, misalignment, bearing wear) generate signatures that transmit through the bearings.
Motor/Pump Casing: Vibration sensors should be placed close to the points of force and wear.
Load Zone: Sensors should be placed on the load-zone side of bearings where potential faults are most likely to be detected.
Machine Train: Monitoring multiple points along the machine train (motor drive end, motor non-drive end, pump bearing) provides a complete picture of an asset’s health.
Secure Mounting
Ensure the sensor is securely mounted directly onto the component (using a stud mount or strong magnet) to ensure accurate high-frequency data collection.
How to Choose a Vibration Sensor
Selecting the right vibration sensor for the application is key to obtaining useful, actionable information. When choosing a vibration sensor for your application, consider the following:
- Criticality of Asset: Highly critical machines should use continuous remote/wireless monitoring. Less critical or spare equipment may use periodic handheld checks.
- Frequency Range: Select a sensor type (accelerometer, velocity sensor or proximity probe) that will accurately measure the expected fault frequencies of the machine, for example, you should select an accelerometer to detect high-speed bearing faults.
- Sensitivity/Measurement Range: The sensor must be sensitive enough to detect minor issues but also capable of handling the maximum expected vibration levels without clipping.
- Environmental Factors: Consider temperature, moisture (IP rating) and hazardous area conditions/ratings (ATEX/hazardous area certifications). Wireless sensors with remote capabilities are ideal for hard-to-reach or dangerous locations.
- Budget and Connectivity: Remote vibration sensors simplify the program by reducing or eliminating the need for technicians to walk the plant taking manual measurements and transferring data. They permit data to be automatically gathered, stored and analyzed, freeing up maintenance teams.
Using Remote Vibration Sensors for Predictive Maintenance
As part of a vibration monitoring program, vibration sensors support a proactive, predictive maintenance strategy, which provides significant operational and financial benefits, including:
Shift in Maintenance Approach: Using vibration monitoring for predictive maintenance, allows you to move from reactive or calendar-based maintenance to a proactive program of predictive maintenance, minimizing unplanned downtime and maintenance labor hours.
Data Automation: Remote sensors automatically gather, store and analyze vibration data continuously.
Real-Time Decision Making: Advanced analytics enable immediate and informed responses to abnormalities.
Labor Savings: Using vibration sensors reduces the need for manual data collection, freeing maintenance teams to focus on resolving issues and preventing future failures.
Optimized Operations: Vibration monitoring-based predictive maintenance programs keep plants operating with high levels of uptime, efficiency and profitability.
JHFOSTER: Your Vibration Monitoring Partner
As the heart of a vibration monitoring program, vibration sensors allow you to apply a more proactive maintenance strategy. Today’s remote vibration sensors automatically gather, store and analyze machine data so maintenance teams can dedicate their time to correcting abnormalities and avoiding future failures, maximizing facility uptime and profitability. For more information on remote vibration sensors and how they can help you develop a effective vibration monitoring program for predictive maintenance, please contact JHFOSTER.
