GB1384575A - Tube bending apparatus - Google Patents

Abstract

1384575 Bending tubes I M MUSSON 9 Aug 1972 37211/72 Heading B3E Apparatus for bending the tangentially extending ends of a coiled tube, so that they lie diametrically across the ends of the coil, comprises a semicircular turntable 4 having a groove 7 in its peripheral wall, a segment 18 with a groove 23 in its peripheral wall detachably secured to the turntable, an arcuate grooved clamp 24 for clamping the coil into groove 23, means 12 restraining non-axial linear movement of the tube, means for rotating the turntable, and a mandrel 8 extending into the end of the coil which is to be bent. In the Figure, the turntable and segment are attached by a pin 20 passing through co-operating inclined projections 16, 19, and the clamp 24 is pulled on to the segment by a two-armed strap 25 and pin 26 having an eccentric end, so that rotation of the pin tightens the strap. The inclination of the projections 16, 19 causes,the groove 23 in the segment to lie at the helix angle of the coiled tube. Clamp 24 has a high friction lining. In operation, the end to be bent is cut to length, heated by gas flames and quenched to anneal and soften it, and a lubricant in aerosol form is sprayed inside the tube. The end is then slid on to the mandrel 8 so that the start of the coil proper fits in groove 23. Clamp 24 is secured, and member 12 pressed against the tube end. An hydraulic motor (not shown) then rotates the turntable through a little more than half a revolution to bend the tube end. Clamp 24 and pin 20 are then removed whereupon the segment 18 can be slid along projection 16 to a position clear of the coil, and removed. The turntable is rotated through a further 90 degrees, member 12 withdrawn, and the mandrel 8 removed by rod 9. The coil can then be removed, and the turntable further rotated to its starting position.