Reactor shutdown device by way of liquid poisons

Purpose: To promote the interruption of nuclear reactions by the injection of liquid poisons. Constitution: In a pressure tube type reactor, exhaust ports are provided axially with an equal pitch to a control rod guide tube securely passed through the top surface of a calandria tank. Further, the pore diameter for each of the exit ports is determined such that the amount of the liquid poisons supplied and exhausted within a reference period of time from a liquid poison feed device is made equal. This enables to inject and admixed the liquid poisons at a predetermined concentration uniformly to each portions of the calandria tank within the reference period of time. (Furukawa, Y.)