The Debugging Of Deep Overhaul To The Type ? Region ? Dose Rate Meters In Nuclear Power Plant

The type ? region ? dose rate meters of ionization chamber which are in charge of monitoring the ? dose rate of refueling platforms and the surface of the pools when refueling are an important part of radiation monitoring system in nuclear power plant.Components for type II region ? dose rate meters were manufactured in 90 s last century,which breakdown frequently since running.Different of application failures were found in 80% of maintenance history which cause the meters unreliable.This article simply introduced the compositions of the ionization chamber monitor,and also discuss the main points of overhaul.Based on overhaul of pre mu-circuit and centralized compute subassembly,theoretical arithmetic and spot test after the faults of monitor were solved.The difference between theoretical value and response to the source of the monitor was narrow down.This article provides thinking and method to overhaul of this type of monitor,and also play a role in preventive maintenance.Through sever times' on-site maintenance and fault handing,way to repair the monitor was grasped,and the theory was proved.Overhaul to the monitor during preventive maintenance window,and data statistics during this article was written,failure rate of this type of monitor drop by 30%.