| 摘要 |
<p>A method and an apparatus for gauging the amounts of material which are lost due to corrosion and/or erosion in the course of a determined period of time, utilise a piece of material (1) which has previously been made radioactive, and a radiation intensity meter (3, 4) disposed at a measuring site a fixed distance from said piece of material for measuring the radioactive radiation from said piece both at the beginning and at the end of said period of time. Each of said measurements is calibrated by means of a further radiation source (6) disposed for controllably adopting either a most radiation screened position or alternatively a least screened position with respect to a radiation screen (2) and thereby providing a known radiation intensity at the measuring site in both positions. The least radiation screened position preferably provides complete unscreened radiation intensity at the measuring site, whereas the most screened position provides negligible radiation intensity at said site. The measuring results in the two positions are mutually compared in order to deduce the contribution of said piece of material (1) to the combined radiation source. The further radiation source is then constituted by a calibration member (6) composed of the same material as the piece of material (1) which is exposed to corrosion and/or erosion, the calibration member being radioactivated at the same time and by the same activation process as said piece (1). The calibration member (6) is preferably dimensioned to provide at all time the same radiation intensity at the measuring site as a predetermined material loss from said piece of material (1), e.g. a prefixed thickness reduction of the same.</p> |
