Cool Cosmos

Maintenance of Mechanical Systems

Courtesy of Sierra Pacific Infrared and Inframetrics
(Top or left) Infrared view of the Space Shuttle returning to Earth after descending through the atmosphere. The white and red areas of this false-color image reveal the hottest sections, which are clearly the nose and the engines. Note the thermal "reflection image" of the Shuttle on the pavement! (Bottom or right) A close-up thermal image of an automotive engine after it has been idling. The white/red areas are the hottest, while the blue areas are the coolest. Note how the insulated ignition wires to the spark plugs (lower left of the image) remain cool, even though they are next to the hot engine block.

Thermal infrared images play an important role in testing and monitoring mechanical systems. Measuring the heat output of various parts of a system can show where the individual components may be weak or faulty, allowing for repairs to be made before the system breaks down. For example, ball bearings are important elements in many machines. Friction in bearings causes an increase of the temperature inside the bearing. Excessively high temperatures in a bearing may cause it to fail. Electric motors, gas turbine engines, belts, conveyors, gears and radiator cores can all be tested at infrared wavelengths. In the automotive industry, IR testing is performed on engines, tires, and brakes as well as on air conditioning and heating systems. Infrared imaging is used to check pipelines for cracks and leaks, in inspections and for the testing of cooling losses in large storage freezers.