Application of thermography to predictive maintenance

During routine predictive maintenance, engineers often performed condition-based monitoring, such as vibration analysis, to improve their understanding of machine conditions and improve the reliability of their equipment. But did you know that there is also another type of condition-based monitoring that can be applied to your predictive maintenance solution? That's right, it's thermography.

What is thermography?

Thermography is a solution where remotely scanning machine components such as panels, modules and cables and observing the thermal gradients of the scanned image will give an idea about the functioning and performance of the equipment.

Why is thermography useful?

Vibration analysis detects machine failures by detecting machine vibration patterns to determine the root cause of equipment failures. However, there are mechanical or electrical faults that cannot be seen with the naked eye, such as those that constitute infrared.

Infrared is an invisible portion of the light spectrum that is invisible to human eyes but that we can perceive as heat . All objects hotter than absolute zero will emit energy within the spectrum. The hotter the object, the brighter the thermal infrared scanner will be.

With thermal imaging, we can immediately see which component is problematic without disassembling machines and locate mechanical and electrical problems quickly and accurately. Furthermore, thermography is performed without direct contact with the equipment or component. Therefore, it is a safe and reliable method that can be performed during production.

Use of thermography in various applications

Thermography is used in a wide range of applications:

• Electrical components, including power plants, transmission lines, networks, control panels, components and printed circuit boards
• Mechanical equipment, such as rotating equipment, sealers and conveyors,
• Refractory-lined structures, such as ovens
• Doctors like body exams
• Buildings such as heat leaks, moisture/mold, pipes and ducts

Choose a thermal imager

A thermal imaging camera detects and corrects electrical and mechanical defects. Thermography converts invisible radiation into a visible image by using sensors to convert electronic signals into an easy-to-view image.

Thermal imaging cameras must be chosen carefully, taking into account the applications. Some factors and features to consider are:

• Hardware and software
• Reporting, interfaces and connectivity
• Accuracy and resolution
• Temperature range
• Camera visual functionality
• In-camera editing function
• Ergonomic design and ease of use
• Comments/notes/annotations functionality
• Accessories / Assistance / Support / Training

A real-world example

More recently, a well-known food and beverage company had to close its factory for half a day due to an unexpected failure in one of its control panels, resulting in a significant loss of production. To prevent such incidents from happening again, our team performed a thermal inspection as part of the company's long-term predictive maintenance program, checking the condition of all operational electrical components to detect problems early.

Some factors to pay attention to

There are some factors that can contribute to unexpected failures in electrical equipment. To obtain an optimal result from your electrical component without having to turn off the circuit breaker (i.e. let it run), you must make sure that:

1. Not overloaded
2. Loads are balanced and evenly distributed
3. The cable insulation is not damaged

Applying thermography: a long-term gain

Along with other condition-based monitoring activities, applying thermography to your long-term predictive maintenance solution will provide the benefit of achieving peak equipment performance and increasing productivity. By identifying electrical and mechanical problems quickly and accurately, thermographic inspection can prevent unexpected downtime that leads to huge production losses.