Research and practice of overpressure protection system for EPR primary hydrostatic test

Abstract

According to the requirements of design and construction rules for mechanical components of pressurized water reactor nuclear islands, the primary hydrostatic test must be carried out before and after the operation of nuclear power plant. The overpressure protection system is used to prevent the accidental overpressure of the primary circuit during the hydrostatic test, and to alleviate the serious consequences of overpressure on the involved test equipment. The system design and equipment selection for the primary circuit of the third generation nuclear power plants are much different from that of the second generation ones. In addition, the construction of the third generation nuclear power plants is too late to have the reference experience. Based on the control characteristics of the primary process system in European pressurized water reactor and the deficiency of the overpressure protection system in china pressurized water reactor, the research work is conducted from the hereafter aspects, the pressure control strategy of the primary hydrostatic test, scheme design of the overpressure protection system, commissioning and site application. And it is also applied in the primary hydrostatic test of a nuclear power plant. The practical results show that the implementation principle of the overpressure protection system is correct, the analysis of risks and various countermeasures is appropriate, and the implementation scheme is feasible. The research work and practice can provide some reference for the subsequent project construction.