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

FIELD: machine engineering.

SUBSTANCE: apparatus includes mechanism for feeding tube along its axis; mechanism for rotating tube; cut-off unit having cut-off sleeve with annular cutter embracing tube and cut-off roller. Said roller is mounted at side of separated tube blank with possibility of free rotation in bearing assemblies and it includes mechanism for its inlet to tube and for its outlet from tube and also mechanism for feed-in of said roller. The last mechanism is in the form of positively rotating sleeve with opening eccentrically arranged relative to rotation axis of sleeve and used for mounting cut-off roller in bearing assemblies. Cut-off roller includes two, inner and outer cutters mounted with possibility of arranging inside and outside tube blank. Inner circular cutter and outer annular cutter have cutting edges arranged in the same plane. Cut-off apparatus is provided with two-step mandrel having circular cutter in its end. Said mandrel may be mounted in tube with tightness in such a way that its end rests upon cut-off roller.

EFFECT: prevention of significant change of diametrical dimensions of tube and tube blank at cutting-off.

1 dwg