Applying thermography to predictive maintenance

 

Technicians who practice infrared predictive maintenance regularly check the temperature of critical equipment, allowing them to track operating conditions over time and quickly identify unusual readings for further inspection.

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, extend the lifespan of machine assets, and further maximise maintenance and production.

To actually save money, predictive maintenance should not create excessive additional maintenance efforts. The goal is to move 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 imager.

A thermal imager takes non-contact, infrared temperature measurements that capture an object’s temperature profile as a two-dimensional picture. It can capture temperature from both critical components and the entire integrated unit. Thermal imagers can also store previous and current images for comparison and upload images to a central database.

 

Cost savings

Some studies in the US estimate that a properly functioning predictive maintenance program can provide savings of 30 to 40% over reactive maintenance. Other independent surveys indicate that, on average, starting an industrial predictive maintenance program results in the following savings:

• Return on investment: 10 times

• Reduction in maintenance costs: 25 to 30%

• Elimination of breakdowns: 70 to 75%

• Reduction in downtime: 35 to 45%

• Increase in production: 20 to 25%

 

Integrating thermography into PdM

Infrared thermography cameras are a first line of defence in a predictive maintenance program. Technicians can quickly measure and compare heat signatures for each piece of equipment on the inspection route, without disrupting operations.

If the temperature is markedly 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.

Applications

• Monitor and measure bearing temperatures in large motors or other rotating equipment

• Identify 'hot spots' in electronic equipment

• Identify leaks in sealed vessels

• Find faulty insulation in process pipes or other insulated processes

• Find faulty terminations in high power electrical circuits

• Locate overloaded circuit breakers in a power panel

• Identify fuses at or near their current rated capacity

• Identify problems in electrical switch-gear

• Capture process temperature readings.

 

Inspection process

•  Begin by using existing lists of equipment from a computer managed maintenance system (CMMS) or other inventory tool.

•  Eliminate items that are not well suited for infrared measurement.

•  Review maintenance and production records. Prioritise key equipment that is prone to failure or often causes production bottlenecks.

•  Use a database or spreadsheet to group critical equipment, either by area or function, into roughly 2 to 3h inspection blocks.

•  Use a thermal imager to capture baseline images of each piece of critical equipment. 

•  Download the baseline images into software and document the route with location descriptions, inspection notes, emissivity and RTC levels and alarm levels if appropriate.

•  When the next inspection is due, if the imager supports uploading, simply load the previous inspection images onto the camera and follow the onscreen prompts.

Fluke thermal imagers feature Fluke Connect. Measurements can be wirelessly transmitted to the Fluke Connect app on smartphones or tablets and automatically uploaded to FlukeCloud Storage, eliminating transcription errors. Technicians can collaborate in real time with colleagues with ShareLive video calls, increasing productivity in the field. Fluke also offers IR-Fusion, a technology that fuses a visible light image with an infrared image for better identification, analysis and image management, and SmartView full analysis and reporting software.