WIRELESS CONDITION MONITORING
WIRELESS CONDITION MONITORING
Wireless sensors can help discover maintenance issues before they happen by supplying real-time information, says John Bernet.
C
ondition monitoring is the best way to proactively determine when machines need maintenance. Collecting real-time data on an asset’s condition provides an accurate, up-to-date picture of asset health. Regardless of the type of asset, condition monitoring is the best solution to reduce unplanned downtime and production gaps. Machines monitored by wireless sensors can let a user know the machine needs to be inspected or maintained. When equipment is continuously monitored with wireless sensors, users are alerted to changes or deviations from the norm. Once installed, they monitor assets 24/7 and trigger alarms when conditions reach certain thresholds. Wireless sensors easy to install, even on assets in dangerous or hard-to-reach places and once in place they avoid the need for repeated trips to take measurements. The next steps are to diagnose the potential fault and its severity so users can plan the best corrective action. Numerous technologies can detect machine faults and their severity. By matching the asset and the company’s needs and budget with available technologies, users can boost reliability and maximise maintenance dollars and resources.
Condition-monitoring methods Predictive technology methods that detect potential faults early are not always the best choice. Striking a balance between the amount of warning about the fault and the time and money needed to spend to diagnose the fault is key. So, what condition-monitoring methods might fit the company’s needs?
UK2
November 2019
Here are some technical considerations for four common methods: 1. Oil analysis is capable of detecting faults early. Monitoring lubricant, wear, and contamination offers a multifaceted look at asset condition and can alert users to potential issues before any actual damage occurs. Oil analysis can be useful for low-speed machinery (<5 rpm), where vibration analysis may be difficult. Obtaining oil samples and interpreting oil analysis data can be complex, and using a lab brings additional costs. Not all assets have oil that can be analysed. 2. Ultrasound analysis can discover things oil analysis can’t, such as bearing wear or fatigue so early that it is often too soon to replace the bearings. Increased decibel readings can indicate a potential fault resulting from friction. Ultrasound can detect leaks by identifying sounds at frequencies that wouldn’t be heard in a plant’s ambient noise. Ultrasound can be useful for low-speed machines. 3. Vibration monitoring analysis is well established, so vibration patterns and anomalies are well documented. Vibration analysis also can identify the most common mechanical faults. It identifies faults 12 to 18 months in advance, which allows of time to react while there is still life in the asset. 4. Thermography can uncover electrical hot spots, faulty connections, overheated bearings, pipe blockages, issues with tank levels and other issues. Use vibration combined with thermography for rotating machines to avoid asset damage. Wireless sensors can communicate realtime information related to all of these methods. By monitoring measurable
www.controlengeurope.com
conditions, such as capacity, temperature, pressure, or sound, and sending a signal when the relevant quality changes or reaches a certain threshold, wireless sensors make it possible to users to know about potential faults right away. When making changes to a maintenance program, a best practice is to start with a small pilot program and grow it over time, rather than attempting to change everything at once. Recommended steps include: 1. Conduct a criticality analysis. It makes sense to keep the closest eye on the assets that have the most significant impact on the bottom line. If they aren’t being continuously monitored already, these assets are good candidates for wireless sensors. 2. Identify probable asset failures. 3. Decide on the technology best suited to identifying these failure modes, keeping in mind the team’s experience and the budget. 4. Trend and analyse the data from the wireless sensors to plan and execute maintenance actions at the most advantageous times, reducing unplanned downtime and extending the life of the assets. ! John Bernet, CMRP, is a mechanical application and product specialist at Fluke Corp. This article originally appeared on www.controleng.com
Wireless sensors are easy to install, even on assets in dangerous or hard-to-reach places. (Image courtesy: Fluke Corp) Control Engineering UK
