Diagnosis system equipment (ASTD) for reactor coolant pumps (RCPs)

Diagnosis system equipment (hereinafter referred to as ASTD) is a part of diagnosis system intended for NPP RCPs diagnosis (hereinafter referred to as RCP STD) via thermal and vibration monitoring, retrieval of diagnostic messages about RCP state, and vibration level exceeding warning.

The diagnosis system equipment ASTD including the system and application software (developed by CDBMB) fulfills the following functions:

  • monitoring of RCP state and generation of preventive and emergency alarms
  • generation of «dry contact signal» on achieving the preventive and emergency vibration levels and displaying it on MCR panels
  • monitoring of hardware state
  • transmission of RCP STD failure signal to upper-level control system
  • receipt of thermal monitoring parameters and information about pump valves condition from upper-level system
  • simultaneous analysis of thermal and vibration monitoring parameters for pumps health assessment
  • display of pupms status (diagnosis messages) to operators
  • non-stop data archiving

ASTD is used for measuring absolute and relative vibration of RCPs using accelerometers and eddy-current converters.

For the period from 2007 to 2020 FSUE «Alexandrov NITI» produced 18 equipment sets for Russian and foreign NPPs. Many years of equipment operation under demanding NPP conditions have demonstrated its high reliability.

ASDT includes:

  1. set of primary transducers (56 pcs.) with connecting cables
  2. junction boxes with signal converters (4 pcs.)
  3. уremote work station
  4. SPTA set
  5. data acquisition station of vibration monitoring system
Absolute vibration measuring channels (sensors: AS-063 or AS-073, MB-44M-1)
Number of channels, pcs. 28
Measuring range of vibration velocity, mm/s 0.5 to 50.0
Frequency range, Hz 10 to 1000
Admissible absolute error of vibration velocity measurements, mm/s ±(0,1+0,1×Vmsrd), where Vmsrd – measured vibration velocity, mm/s
Non-uniformity of amplitude-frequency response
as per GOST ISO 2954:
−1.01 to −5.01 at frequency of 10 and 1000 Hz;
+0.83 to −0.92 at frequency of 31.6 and 79.4 Hz;
+0.81 to −0.94 at frequency of 398 Hz;
−0.14 to −1.89 at frequency of 794 Hz
Relative vibration measuring channels (eddy-current converters SD 052/OD 054 or SIEL 166D/SIEL 1661N)
Number of channels, pcs. 24
Displacement measuring range, mm −1.0 to +1.0
Basic admissible absolute error of displacement measurements, mm ±(0,02+0,05×Xmsrd), where Xmsrd – measured vibration displacement, mm
Vibration displacement range, mm 0.05 to 0.35
Basic admissible absolute error of vibration displacement range, mm ±(0,02+0,07×Smsrd), where Smsrd – measured vibration displacement, mm
Frequency range, Hz 10 to 200
Rotation speed measuring channels (eddy-current converters SD 052/OD 054 or SIEL 166D/SIEL 1661N)
Number of channels, pcs. 4
Rotation speed measuring range, rpm 20 to 1200
basic percentage error of rotation speed measurements, %, at most ±1
Total number of measuring channels 56