FIELD: measurement equipment.
SUBSTANCE: three packets of fibre web are prepared; two packets of fibre assumed as a reference, and one - controlled fibre, besides, one packet of the reference fibre shall have the number of layers, providing for maximum, and the second one - providing for minimum variation of an acoustic signal in the control range, from the packets of reference and controlled fibre they cut the necessary quantity of samples of the specified size and configuration, all produced samples are maintained during the required time under identical climatic conditions, laid into a cassette with two cells, the first of which serves for laying of the reference sample, and the second one, having acoustically transparent cover liners of the air capacitor, for laying of the controlled sample, a reference sample with maximum number of layers is laid into the first cell, into the second one they lay the reference sample with minimum number of layers, the first and second cells are scanned in series, the range of acoustic signal control is calibrated, then the reference fibre from the second cell is replaced for the controlled one, scanned, according to the readings of impedance and available characteristic of impedance of the air capacitor from weight, the produced acoustic signal is normalised by weight to the normative one, and the result is found as the ratio of signals via the maximum reference sample to the signal via the control sample.
EFFECT: higher accuracy, objectivity and efficiency of control under laboratory conditions.
3 dwg
