Use of the gamma-radiation back-scatter measuring method for determining the density distribution of derived timber product board

摘要

Use of the gamma-radiation back-scatter measuring method for determining the cross-sectional density distribution of derived timber product board, especially of chipboard and fibreboard in the course of continuous preparation. The measurement is carried out on an edge-forming section face. The cross-section of the measuring gamma radiation is small compared to the thickness or, in the case of multilayer board, to the layer thickness of the derived timber product board. The section face is scanned by the measuring gamma radiation in the thickness direction of the derived timber product board. The measuring gamma beams are directed onto the section face with an oblique angle of incidence and the back-scatter beams are received by at least one gamma-radiation detector in a back-scatter emergent-angle range which approximately coincides with or is smaller than the angle of incidence. A computer to which the gamma-radiation detector feeds the measured values, compares the measured values with stored target values which represent a measure for the density. <IMAGE>