Condition monitoring (CM) is the process of monitoring machinery; such that a specific type of change becomes indicative of a developing failure. CM is a major component of predictive maintenance. Heat is one of the most important indications of failing components. As such, thermography can be successfully applied to the monitoring of high-speed bearings, fluid couplings, conveyor rollers, electrical contacts and terminations, motors and engines, and many other industrial processes.
The use of condition monitoring allows maintenance to be scheduled, or other actions to be taken, to avoid the consequences of failure before the failure occurs. Machines with defects are more at risk of failure than defect free machines. Intervention in the early stages of deterioration is almost always more cost effective than allowing the machinery to fail. Thermographic condition monitoring has a unique benefit in that the actual heat dissipation that represents normal service can be seen; as such, conditions that would shorten normal lifespan can be addressed before failures occur.
Condition monitoring using IR thermography provides a quick and safe way of detecting problems in many different situations. Modern infrared cameras can be used to detect increases in temperature that indicate potential problems. Being non-contact, thermography provides a condition monitoring technique that can often be safely carried out while equipment is running; thus, reducing the requirement for predictive maintenance outages. In turn, this ultimately decreases costs in payroll and production losses.
Image 1 This thermal image of an electric motor highlights a bearing problem. Further investigation using vibration analysis confirmed the thermogram. Lubricant analysis determined that the lubricant was contaminated.
Image 2 The above thermal image of a large tank clearly shows the level of the liquid (red area) and buildup of sediment and scale below (green area).
Image 3 Finding bad electrical connections like the one in this thermal image is a very common application for thermography.