Many maintenance shops now own thermographic cameras. In the early days of thermography, the equipment was bulky and expensive. Today's devices are affordable and easy to carry. As good as today's thermographic cameras are, it's important to understand that they don't actually do thermography. They are tools a thermographer uses.
If you don't have a trained thermographer on staff, consider sending someone to thermography school or having several maintenance techs attend classes held at your facility. Some of the things a thermographer must know include:
- Various laws of physics related to heat transfer.
- The difference between emission, transmission, and reflection.
- How radiometry affects the images.
- How to resolve spatial issues.
- The effects of convection and how to adjust for them.
- Types of emitters: specular, diffuse, Lambertian.
- Angular sensitivity in emissitivity.
- How to perform emissivity calculations.
Yes, you can find a hotspot without knowing these things. But how hot in relation to what? Is what you’re seeing really a problem, and how severe is it?
