Patent Number: 054694809
Section: abstract

The currently used atomic reactors has to be refueled periodically. During this refueling, the checking and repair of the major sections of the atomic reactor are carried out, and therefore, a low water level operation, i.e., mid-loop operation, is carried out for removing the residual heat. According to the present invention, a round-about pipe conduit is additionally installed between a suction pipe conduit and a discharge pipe conduit of the residual heating removing pump, and a flow rate adjusting valve is installed on the round-about pipe conduit. Thus the flow passing through the pump is maintained at the normal operation level during the mid-loop operation, while, as the residual heat is decreased, the round-about flow rate is gradually increased until the suction rate from the hot leg can be maintained at a proper level, thereby preventing the introduction of air into the residual heat removing pump.