Ronald L. Predmesky

Pulsed thermographic inspection of spot welds

In automotive manufacturing, the lack of nondestructive methods for assessment of spot weld integrity has been a critical shortcoming, with enormous economic consequences for both domestic and foreign auto makers. At present, auto body welds are subjectively evaluated using destructive pull tests, or visual examination after the weld has been mechanically separated using an impact tool. Pulsed thermographic evaluation of spot welds offers a fast, noncontact method for quantitative assessment of the weld nugget. The technique can be applied using either one or both faces of the weld. Results on steel resistance welds will be presented, along with correlation to weld process parameters.

Infrared in automotive applications

As the automotive industry continues to develop advanced materials and manufacturing processes, infrared imaging has the potential to become a major tool in process monitoring and closed loop process control. This paper reviews five novel applications of infrared imaging in applications such as product testing, component manufacture, and vehicle assembly. Infrared was found to be effective as a diagnostics tool for characterizing disc brake systems and electronic engine control sensors. The effectiveness of infrared to qualify fuel nozzle backspray was used to optimize hardware design for fuel systems. Finally, infrared was found to be useful in vehicle assembly operations in the installation of windshield glass and instrument panel hardware where visual inspection was impractical. The speed of image capture and the availability of image processing software for real time image processing and closed loop process control will no doubt find more applications as infrared imaging finds its niche in the automotive industry.