JP2525277B

• Main Authors: GUNJI MINORU, SAITO MAKOTO
• Format: Patent
• Language: English
• Published: 14.08.1996
• Edition: 6
• Subjects: GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PHYSICS; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

PURPOSE:To enable confirmation of functional integrity of a curie point electromagnet in a reactor during an actual reactor operation period by heating the electromagnet over the activation temperature with a heater during the term of drawing up in an upper guide tube. CONSTITUTION:During a normal operation, an electromagnet 12 having the curie point quickly responds to temperature abnormality in a fuel assembly and is set in the mainflow of high temperature coolant passing through the fuel assembly. If the coolant temperature abnormally increases to exceed the curie point, the temperature sensing magnetic material turns to non-magnetic and removes an armature 22 to drop a connecting control rod in the core, and thus the reactor is emergently shut down. On the other hand for function confirmation purpose, the electromagnet 12 is drawn up in an upper guide tube 14 to heat the electromagnet 12 over the curie point temperature of its temperature sensing magnetic material with a heater 18 for heating. If the function is normal, the armature 22 is removed off. By this, confirmation test for functional integrity of the curie point electromagnet is possible during an actual reactor operation period.