摘要 |
Raw material to be expanded is supplied to an expansion chamber (12). The volumetric weight (M) and the moisture content (F) of the expanded material is measured, and signals representing the measured values obtained, are supplied to a microcomputer (27). This is programmed for comparing the volumetric weight as measured with a nominal value of the volumetric weight at the prevailing moisture content of the expanded material and is adapted to supply in dependence of the comparison made a signal for controlling the screw conveyor and drive unit (11, 13) for the supply of raw material to the expansion chamber to control the expansion of the material in dependence of the comparison by increasing or decreasing the amount of raw material supplied per unit of time. |