Nuclear power plant device cooling water system

The utility model provides a nuclear power plant device cooling water system. The system comprises a connecting pipeline, an RRI/SEC heat exchanger arranged on the connecting pipeline and a cooler condenser. RRI side entrance and exit of the RRI/SEC heat exchanger are connected by a bypass pipeline to form a bypass branch which is connected in parallel with the RRI/SEC heat exchanger. The bypass pipeline is provided with a valve which controls on and off of the pipeline. RRI side entrance and exit of the cooler condenser are connected by a reflux pipeline to form a reflux branch. The reflux pipeline is provided with a reflux pump which drives device cooling water to flow from the RRI side exit of the cooler condenser back to the entrance of the cooler condenser through the reflux pipeline. According to the nuclear power plant device cooling water system provided by the utility model, the combination of bypass and reflux is used to realize temperature regulation of device cooling water; a unit can normally run