APPAREIL D'ETUDE DE LA PROPAGATION DES FISSURES DANS LES PLAQUES EPAISSES D'ACIER POUR ENCEINTE SOUS PRESSION

• Main Author: ERIC JOHN ROBBINS, ALAN MARKHAM CLAYTON, WILLIAM PAUL WHITE ET ROBERT EDWIN LECKENBY
• Format: Patent
• Language: French
• Published: 02.11.1984
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

L'INVENTION CONCERNE LES APPAREILS D'ETUDE DE LA PROPAGATION DES FISSURES.ELLE SE RAPPORTE A UN APPAREIL QUI COMPREND UN MOTEUR ENTRAINANT UNE BROCHE VERTICALE CREUSE 8 QUI PORTE L'ECHANTILLON S A EPROUVER SOUS FORME D'UN CYLINDRE DONT L'EPAISSEUR EST EGALE A L'EPAISSEUR DES PLAQUES DONT ON VEUT ETUDIER LE COMPORTEMENT. L'ECHANTILLON S EST ENTRAINE A UNE VITESSE DE ROTATION DE PLUSIEURS MILLIERS DE TOURS PAR MINUTE, PAR LA BROCHE, DANS UNE ENCEINTE 11 DANS LAQUELLE PENETRE DE L'AIR CHAUD, UN CHOC THERMIQUE ETANT OBTENU PAR PROJECTION D'EAU SUR L'ECHANTILLON CHAUFFE. UN DISPOSITIF 19 AMORTIT LES VIBRATIONS.APPLICATION AUX ESSAIS DES MATERIAUX UTILISES POUR LES ENCEINTES SOUS PRESSION TELLES QUE LES CUVES DES REACTEURS NUCLEAIRES. Equipment for investigating crack propagation in thick steel plates of a material with applicability for pressure vessels comprises a test specimen in the form of a hollow cylinder of the material under investigation, a vertical spindle from which the hollow cylinder is suspended and which can be rotated at a speed of the order of thousands of revolutions per minute, damping means for damping against flexural resonance vibrations of the cylinder and spindle, a container for the cylinder and means for supplying hot air to the container via a port, means for applying through a port in the container, a jet of cold fluid on to a surface of the cylinder to apply thermal shock thereto the spindle being hollow to accommodate leads from instrumentation on the cylinder to a slip ring unit from which leads to control and recording equipment extend, the instrumentation serving to monitor crack propagation under the conditions of high speed revolution which induce a hoop stress in the material approaching its yield strength, and the thermal shock applied thereto.