METHOD AND APPARATUS IN THE MANUFACTURE OF A FIBRE FELT

摘要

A method in the production of a mineral fibre felt, said method utilizing a continuous measurement of the distribution of fibres over the width of the primary fibre web. A measurement apparatus suited to implement the method comprises a first light source (9) and a detector (10) placed on opposite sides of the primary fibre web so that the plane defined by the measurement sector of the detector (10) does not intersect the emissive surface (e) of the light source (9). The detector (10) measures the forward scattering of light around an angle alpha at several points distributed over the width of the primary fibre web. The measured scattering of light correlates with the number of fibres in the web. The measurement result is employed to control the fibre production to the primary fibre web and for the formation of the secondary fibre web.