Vorrichtung zur zerstoerungsfreien Werkstoffpruefung von Walzgut

摘要

1,215,146. Photo-electric flaw determination. AUTOMATION INDUSTRIES Inc. Dec. 11, 1967 [Dec.30, 1966], No.56247/67. Heading G1A. Internal flaws of a steel sheet cause irregulaties in the thermal conductivity of the sheet and consequently variations in the surface temperature as heat flows from one surface to the other. Flaws are detected by measuring the temperature over one surface as a sheet cools naturally or is either heated or cooled on its other surface. Three photo-electric devices sensitive to infrared radiation may scan respectively the two edges and centre line of a moving steel sheet or alternatively a single photo-electric device may be oscillated to scan back and forth across the width of the moving sheet.