TUBE BLANK CUTTING OFF METHOD Russian patent published in 2007 - IPC B23D21/04 

FIELD: machine engineering.

SUBSTANCE: method comprises steps of feeding cylindrical tube to opening of receiving sleeve having in cut-off plane cutting edge till resting upon cut-off roller having in cut-off plane cutting edge; driving receiving sleeve with cylindrical sleeve and cut-off roller to rotation; mounting mandrel inside cylindrical tube with interference fit; placing outside separated blank cut-off sleeve having opening and rigidly joined with cut-off roller. Mandrel and cut-off sleeve are provided with cutting edges in cutting plane; diameter of opening of cut-off sleeve is equal to diameter of receiving sleeve or less than it. Cut-off roller and cut-off sleeve are imparted to additional rotation around axis parallel to rotation axis of cylindrical tube and spaced from it by distance consisting of 3/4 of cylindrical tube wall thickness or more. Revolution number of receiving sleeve exceeds revolution number of cut-off roller with cut-off sleeve by 2 times.

EFFECT: possibility for keeping size of blank at cutting it off.

1 dwg