Reprinted from Foundry Management & Technology, Sept. 11, 2006

Investment Casting Temperature Measurement

Ralph A. Felice, FAR Associates

Successful investment casters know the importance of process control in making quality castings. Key variables in the foundry include metal temperature, mold temperature, mold insulation characteristics, cycle timing, and operator technique. This paper addresses what many consider the most critical of these process variables: metal temperature. Non-contact measurement of metal temperature for investment casting presents numerous significant difficulties; the magnitudes of the temperature errors these cause have not been appreciated until recently. Now, the SpectroPyrometer, an expert-system multi-wavelength pyrometer with hundreds of single-wavelength detectors integrated into one package has been successful in resolving these difficulties. This novel pyrometer also provides quantitative feedback of real-time accuracy and indicates potential problems. The instrument pays for itself in days.