FEED WATER HEATER PIPING SYSTEM FOR NUCLEAR POWER PLANT

摘要

PROBLEM TO BE SOLVED: To eliminate a problem such as radiation exposure due to a large quantity of piping by making the capacity of an emergency system smaller than that of a service system in a drain system of a feed water heater in a BWR plant. SOLUTION: In a BWR plant having a service system drain pipes 14a, 14b, 14c successively carrying drain of a high pressure system feed water heater 12, a second low pressure system feed water heater 10, and a first low pressure system feed water heater 9, and having emergency system drain pipes 15a, 15b, 15c discharging the drain of the feed water heater 12, 10, 9 directly to a steam condenser 5, the capacities of the emergency system drain pipes 15a, 15b, 15c are made to be smaller generally by 40% of the capacities of the service system dram pipes 14a, 14b, 14c. Therefore, with decreasing the area of inner surfaces of the emergency system pipes 15a, 15b, 15c, radiation exposure is reduced and safety is improved.