VIDEO-RADIOGRAPHIC PROCEDURE AND EQUIPMENT FOR THE QUALITY CONTROL OF WELD SEAM

摘要

Abstract:The present invention relates to a video radiographicprocedure for the quality control of welds. The weld seamis transilluminated, point by point, with X-ray or gammaray radiation. Electrical signals representing the radio-graphic image of the weld and its environment are produced.The images are stored and displayed simultaneously. Theinvention is characterized in that two radiation sourcesof identical intensity are used. These two sources ofradiation are pointed towards the weld seam at an angle.The sources of irradiation are perpendicular to thelongitudinal axis of the weld and are symmetrical aboutthe vertical axis. The target plate of a video camera islocated symmetrically to the same vertical axis parallelto the longitudinal axis and the transverse axis of theweld. In such a way that the axes of the radiationsources lie in a common plane with the axes of the targetplate. The first radiation source is operated in a pulsemode and radiographic still pictures are obtained andconverted into electrical signals which are stored. Thesecond radiation source is then operated in a pulse modeand each of the two memorized images is compared to areference standard which has previously been obtained froma flawless weld having the same parameters.