Radioisotope sensor for measuring the density of paper and cardboard web based on the isotope Pm 147 A362 CAN LEB2

Radioisotope sensor for measuring the density of paper and cardboard web based on the isotope Pm 147 A362 CAN LEB2
Pm 147 A362 CAN (LEB 2)

Brief description

In the radioisotopic density sensor of the paper web A362 CAN (LEB 2) as the active element is used radioactive isotope promethium 147 (Pm147). This allows you to use it with high efficiency for measuring the density of materials of relatively low mass in the range up 200 g/m2.
  • Description
  • Technical characteristics
  • Downloads
  • For compensation of the surface contamination effect of the sensor's windows and the source on the course of the calibration curve is used built-in etalon. It is also implemented the compensation changes of air density in the air gap of measuring device that occurs when the ambient temperature and atmospheric pressure is changing.

    Special construction of the sensor's input window minimizes the effect of the ash content of paper web, and the location of the paper web in the measuring gap, on the sensor's readings, by reducing the impact of the effects of electron scattering.

    Operation conditions

    ambient air temperature, °C

    from +5 up to +50

    relative air humidity at 35 C and lower temperatures without condensation,%

    up to 80


    amplitude of displacement for frequencies below the crossover frequency in the frequency range from 10 to 55 Hz, mm


  • Technical characteristics

    Sensor type




    Used types of beta-radiation sources Promethium 147 (do not supplied by the provider)


    Physical principle

    absorption of beta-radiation


    not more than 18.5 GBq


    2,64 year

    Paper weight measuring range

    40 ÷700 g/m2

    Acceptable limit random error paper weight measurement (2σ):

    - if time constant measurements 1s;

    - if time constant measurements 0,1s;

    ± 0,2 g/m2

    0,5 g/m2

    The dose rate of gamma radiation:

    - on the surface of unit source

    not more than 1 µSv/h

    - at 1m distance

    not more than 1 Sv/h

    Working gap between the emitter unit and the detection unit

    12 mm

    Response time, measured from the time of overlap air gap "E-D" by sheet material before the registration on the screen according to GOST 14336-87

    not more than 30s

    Power supply

    + 24VDC

    Permissible deviation from the nominal value of power supply

    - 10% ÷ + 15%

    Power consumption

    not more than 50W