Preventive maintenance programs have long been recognized as the key to
efficient and reliable operations. While computerized maintenance
management systems have assisted engineering and maintenance managers
in developing these programs, technicians frequently have lacked the
needed tools for effective implementation.
That situation has changed in recent years, thanks to the
development of a range of handheld diagnostic and monitoring equipment
– including thermal imaging cameras – that is relatively inexpensive
and easy to use.
One of the easiest to use and most valuable monitoring tools is the
non-contact temperature monitor. Technicians can use these units to
identify temperature variations in equipment, electrical systems,
heat-transfer surfaces, and structures. Some units also can produce a
digital readout or a thermal image.
Technicians can use the temperature monitor and thermal imaging
cameras to detect a number of developing maintenance problems. They can
clearly identify loose, dirty and corroded connections as hot spots,
either in the image or the temperature reading. Worn bearings in motors
also show up as hot spots. Dirty or plugged areas in heat-transfer
surfaces show up as unusually hot or cold areas. By identifying these
developing problems, maintenance technicians can take corrective action
before the problems result in costly equipment failures.
The cost of system downtime has resulted in the need to identify
developing electrical problems in motors before failures occur. While
test equipment for motors has been available for years, only recently
have advances in computerization resulted in lower costs and greater
Today, equipment is available for energized and de-energized testing
to evaluate motor condition. By performing these tests, technicians can
identify developing problems and schedule service outages or install
replacement units before a failure occurs and interrupts service.
Managers have a range of test equipment for motor testing from which
to choose, depending on the application. Hand-held, infrared
temperature sensors and thermal imaging cameras can help identify
bearings that are overheating and loose electrical connections.
Technicians can use portable analyzers to identify misaligned motor
drives, loose or worn couplings, and worn bearings.
Technology at Work: Infrared Imaging