Three ways to conduct thermal inspections

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There’s no universal solution for all infrared inspections with a thermal camera, also known as a thermal imager. You need to match your method to the type of equipment you’re inspecting and the level of detail you require. That said, three typical methods cover most situations you’ll run into:

1. Baseline thermography
2. Thermal trending thermography
3. Comparative thermography

1. Baseline thermography

Baseline thermography is an excellent place to start for just about any application. First, you scan the equipment when it’s first commissioned or later in the lifecycle when it is working the way it should be, and then use that as a reference point for future inspections. Whether you compare the thermal images on your camera in the field or on your PC using software tools, this baseline approach paves the way to helping you spot anomalies down the road.

2. Thermal trending thermography

Once you’ve set your baseline, you can use thermal trending inspections to compare how temperature is distributed in the same components over time. This can help you detect declining performance over time so that you can hopefully schedule downtime maintenance before the equipment schedules it.

3. Comparative thermography

As you might expect, you scan similar components with your thermal camera under similar conditions and compare the results. This method relies on the idea that you expect similar or identical components under similar loads to have similar temperature profiles. Once you have three or more components, picking up an anomaly is relatively easy. Simple, right? Well, mostly. There’s one more level of complexity to consider: Depending on the components being compared, the actual temperature difference that can be viewed as an anomaly will vary.