METHOD OF HYDRAULIC TESTS OF ROLLED JOINTS FOR TIGHTNESS Russian patent published in 2002 - IPC

FIELD: testing technology; testing rolled joints for tightness. SUBSTANCE: method may be used for manufacture and repair of tube bundles of heat-exchange apparatus in oil refining industry. Said method consists in successive loading of rolled joints by applying axial force to butt of tube on side of rear surface of flange at preset pressure "p_i" of liquid every time reducing the thickness of tube wall over length of rolled band to t₁ - its critical magnitude at which leaks are revealed; then, experimental dependence p_i = f(t_i) for this joint and magnitude of axial force are set; duration of reliable operation is determined by known rate of corrosion of tube material and technical operating parameters of joint; axial force is applied to butt of tube simultaneously with or before delivery of high-pressure liquid to clearance between connected components. Dependence of wall thickness and magnitudes of axial forces and pressure of working liquid set experimentally is confirmed through comparison of actual service life of heat exchange apparatus with rated magnitudes. EFFECT: possibility of obtaining quality-factor information. 3 cl, 2 dwg