Detection device UDPN-07 is intended for monitoring of density of thermal neutrons during refueling at reactor plant in composition of neutron flux monitoring equipment (NFME).

UDPN-07 ensures the monitoring of neutron flux density within the range from 
1 to 1.0·106 cm-2·s-1 (neutr.·(cm2·s)-1) at the dose rate of  background gamma-radiation absorbed in the air  at the place of detection unit location of not more than 1.0·104 Gy·h-1 (1.0·106 R·h-1) at nominal power of reactor plant      (100 %).

UDPN-07 sensitivity for thermal neutrons is (0.5 ± 0.1) cm2 (pulses during 1 s at the flux density of 1 neutron via 1 cm2 during 1 s).

Detection device UDPN-07 consists of:

  • Detection unit BDPN-06, implemented in the form of casing (thin-wall cylinder made of stainless steel). BDPN-06 converts neutron radiation into pulses.

 The appearance of detection unit BDPN-06 is presented on the picture: 

The appearance of detection unit BDPN-06
  • Conversion unit BPH-07, implemented in the form of flat housing, inside of which electromagnetic shield with electronic modules is located. BPH-07 performs the following:
    • amplification of current pulses from BDPN-06;
    • discrimination of noise pulses;
    • generation of output pulses which frequency is proportional to neutron flux density.

The appearance of conversion unit BPH-07 is presented on the picture: 

The appearance of conversion unit BPH-07
UDPN-07 is built-up on the basis of ionization fission chamber KNK15 with radiofrequency cable KAGE-HF.  Length of BDPN-06 cable is 30 meters.