WELDMENTS BRAZING METHOD Russian patent published in 1998 - IPC

FIELD: mechanical engineering; brazing of weldments with forming of space between parts. SUBSTANCE: structure is fitted up with forming of inner space between parts to be brazed and placing of solder between parts. Space is sealed by two welds at end faces. Space is connected with helium leak detector. Mixture of shielding gases is delivered into working space of furnace. Gas mixture contains argon and 2.5-4.0% by weight of helium under pressure. Simultaneously inner space of structure is evacuated. Degree of tightness is checked in process of heating the structure in furnace to solder melting temperature. If structure material or welded seams are leaky, helium from gas mixture gets into evacuated inner space and, from the space, into ionization chamber of leak detector where it is detected by helium detector producing audible signal and providing deflection of pointer on instrument. Tightness of welded structure is evaluated by value of instrument pointer deflection. EFFECT: enlarged operating capabilities.