METHOD OF PRODUCTION OF BIMETALLIC VESSELS Russian patent published in 1997 - IPC

FIELD: diffusion welding, applicable for production of apparatuses and other bimetallic items with ducts located under the cladding layer used to pass the heat-transfer agent in various branches of mechanical engineering. SUBSTANCE: groove 2 is made on the inner surface of vessel 1, before diffusion welding then cladding layer 3 is installed in vessel 1, and steel jacket 4 preliminarily annealed in oxidizing atmosphere is placed in the vessel; after that the edges of jacket 4 and vessel 1 are packed, and vacuum is created between them. The whole assembly is placed in a compression furnace, pressure is raised for a short-time reduction of the vacuumized surfaces, after which pressure is relieved down to the atmospheric one. Then the heating system is switched on, and pressure in the compression furnace is raised again; after an isothermal holding the heating system is switched off and pressure is relieved. After annealing liquid medium, for instance water or liquid mineral oils, are fed to ducts 5 by means of a hydraulic pump; when the preset pressure within 2.5 to 45 MPa is attained, the pump is cut off, and the process is monitored by reference to a pressure gauge connected to ducts 5. EFFECT: facilitated procedure. 4 cl, 4 dwg