Nuclear reactor shutdown system.

摘要

A nuclear reactor shutdown system having neutron absorbing rods (68) affixed to an armature (54) which is held in an upper position by a magnetic flux flowing through a Curie temperature material (84). The Curie temperature material (84) is fixedly positioned about the exterior of duct (36) in an annular region through which reactor coolant flows. Upon abnormal conditions which result in high neutron flux and coolant temperature, the Curie material loses its magnetic permeability, breaking the magnetic flux path and allowing the armature and absorber rods to drop into the core, thus shutting down the fissioning reaction. The armature and absorber rods are retrieved by lowering the housing for the electromagnet forming coils which create a magnetic flux path which includes the inner duct wall. The coil housing then is raised, resetting the armature.