Detection device UDPN-05 is intended for monitoring of density of thermal neutron flux in the channels of ionization chambers at reactor plant operation in working range.
UDPN-05 ensures the monitoring of thermal neutron flux density within the range from 1.0·104 to 3.6·109 cm-2·s-1 (neutr/(cm2·s)) 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-05 sensitivity for thermal neutrons is (3.3 ± 0.3) ·10-4 cm2 (pulses during 1 s at the flux density of 1 neutron via 1 cm2 during 1 s).
UDPN-05 sensitivity for background gamma-radiation at exposition dose rate up to 1.0·103 Gy·h-1 does not exceed 1.5·10-1 s-1/(Gy·h-1) (1.5·10-3 s-1/(R·h-1).
Detection device UDPN-05 consists of:
- Detection unit BDPN-05, implemented in the form of casing (thin-wall cylinder made of stainless steel). BDPN-05 converts neutron radiation into current.
The appearance of detection unit BDPN-05 is presented on the picture:
- Conversion unit BPH-02-01, implemented in the form of flat housing, inside of which electromagnetic shield with electronic modules is located. BPH-02-01 is intended for conversion of current from BDPN-05 into succession of voltage pulses which frequency is proportional to neutron flux density.
The appearance of conversion unit BPH-02-01 is presented on the picture:
UDPN-05 is built-up on the basis of boron compensation ionization chamber of hypersensitivity KNK17-1 with thermo-radiation stable cable with magnesia insulation with input of BDPN-05 cable into BPH-02-01 via KS-1. Length of BDPN-05 cable is 20 meters.