Heat is often an early symptom of equipment damage or malfunction, making it important to monitor in preventive maintenance programs. Using thermal imaging preventive maintenance regularly to check the temperature of critical equipment allows you to track operating conditions over time and quickly identify unusual readings for further thermography inspections.
By monitoring equipment performance and scheduling maintenance when needed, these facilities reduce the likelihood of unplanned downtime due to equipment failure, spend less on “reactive” maintenance fees and equipment repair costs, and extend the lifespan of machine assets.
Here’s the trick: to save money, preventive maintenance should not create excessive additional maintenance efforts. The goal is to transition maintenance resources away from emergency repairs and into scheduled inspections of key equipment. Inspections take less time than repairs, especially if done with a thermal camera.
Return on investment and cost savings
Studies by the Federal Energy Management Program (FEMP), estimate that a properly working preventive maintenance program can lead to savings, to the tune of 30 to 40%. Other independent surveys show that, on average, sustaining an industrial preventive maintenance program results in savings:
You can share this information with your supervisor or clients. To calculate the savings at a facility, estimate the costs of unplanned equipment failures. Then factor in human resources, costs for parts, and lost revenue from specific production lines. It would be wise for the maintenance manager to keep a record of machine asset availability, production output, and the distribution of maintenance dollars and total maintenance costs over time. Those numbers will help you calculate the return on your thermal imaging and maintenance investment.
Integrating thermography into preventive maintenance
Thermal cameras are often the first inspection tool a technician thinks to use as part of their preventive maintenance program. They can swiftly measure and compare heat signatures for all equipment on the inspection route, all without interrupting operations.
If the temperature is noticeably different from previous readings, facilities can then use other maintenance technologies—vibration, motor circuit analysis, airborne ultrasound, and lube analysis—to investigate the source of the problem and determine the next course of action.
For best results, integrate all your maintenance technologies into the same computer system, so that they share the same equipment lists, histories, reports and work orders. Once the infrared data is correlated with data from other technologies, the actual operating condition of all assets can be reported in an integrated format.
To capture the best thermal images, follow these best practices:
(Left) With proper conditions, including direct access and normal loads, problems like this high resistance connector are often easy to locate. (Right) The upper bearing on the far motor is failing, causing the entire motor to overheat. (Photo courtesy Greg McIntosh, Snell Infrared Canada)
Inspecting motor bearings
Checking motor bearings is a relatable example. Start with a newly commissioned and freshly lubricated motor and take a “snap shot” of the motor bearing housing while the motor is running. Use this image as a baseline.
As the motor and its lubrication ages, the bearings become worn and heat-producing friction develops in the motor bearing, causing the outside of the bearing housing to heat up. Take additional thermal images at regular intervals, comparing them to the baseline to analyze the motor’s condition. When the thermal images indicate an overheating bearing, generate a maintenance order to replace or lubricate the bearing housing and reduce or eliminate the possibility of costly engine failure.
Spotting leaky seals and gaskets
Finding leaks in sealed vessels is a “snap” when using thermal cameras. Most leaks develop in or around a gasket or seal. Less often, corrosion will cause a weakness to develop and rupture the vessel.
Either way, a thermal camera can diagnose the problem. To find a leaky gasket or seal, scan the imager along the seal looking for thermal eccentricities. A large change in temperature along the seal or gasket indicates a loss of either heat or cold—the “signature” of a failure.
Source – FLUKE