GEAR TO EXPAND PIPES Russian patent published in 2003 - IPC

FIELD: expansion of articles manufactured from profile pipes in holes. SUBSTANCE: invention specifically refers to profile shut-off valves. Gear includes body with central valve Eccentric members in the form of bushings are put on body. Bushings have collars and engage one another. Eccentric bushings are displaced one relative another in central plane through 120 degrees. Cylindrical rollers possessing conical outer surfaces are mounted on eccentric bushings. Upper and lower bushings are joined to body. Thrust rings are positioned between upper faces of rollers and lower faces of collars. Profile pipes expanded beforehand by hydraulic pressure are expanded in hole by rotation of gear with formation of axial load on it and by simultaneous washout. EFFECT: raised serviceability of gear. 2 dwg