PURPOSE: To prevent generation of crack to the joining part between a plate and structural member to be repaired by covering a plate to cover the part where defect is generated, applying pressure locally from plate surface and generating heat energy on contact surface while applying energy.
CONSTITUTION: An electrode 10 is placed at the working place by a slide mechanism 26. The electrode 10 to be brought into contact with a covering plate 3 is set to the covering plate part, an electrode 11 to be brought into contact with a structure is brought into contact with the surface of structure. A pressure imparting mechanism 14 is provided to the electrode 10 to be brought into contact with a covering plate 3, pressure is locally imparted on the contact surface between the covered plate 3 and structure 2. While electric current is caused to flow under pressurisation, resistance heat is generated due to electric resistance of this contact part, the covered plate 3 and structure 2 respectively are locally melted to form a joining part 15. This series of working is monitored by a monitoring mechanism. By this method, the structure of nuclear reactor pressure vessel, which is subjected to irradiation of neutrons so as to generate defect of crack, is prevented from further propagation of crack and generation of crack at repairing.
OKAMURA HISANOBU
MATSUMOTO TOSHIMI
SATSUTA HISATAKA
NAKAMURA MITSUO
KONUMA AKIRA
KONUMA TSUTOMU
KATO TAKAHIKO
KANEDA JUNYA
SUZUKI KUNIHIKO
