GB608886A - Improvements in or relating to oxygen cutting machines - Google Patents

Abstract

608,886. Perforating by fusion. HANCOCK, L. J.; and CUMBER, W. F. Feb. 12, 1946, No. 4382. [Class 83 (iv)] A blow-pipe cutting machine for cutting holes in circular pipes comprises a frame having supports adapted to be rested on the pipe and a blow-pipe carrier journalled in the frame and rotatable about an axis intersecting the pipe, the blow-pipe being reciprocably mounted in the carrier and moved by a link device connected to the blow-pipe and pivoted about a relatively fixed point so that as the blow-pipe moves the nozzle is simultaneously raised and lowered in accordance with the pipe contour. The blow-pipe 12, which may be angularly adjustable for bevel cutting is carried on a head by a tube 14, which is vertically movable through rollers 17 in a slide 15 radially adjustable on graduated bars 16 on a ring 9 rotatable through gearing by a hand-wheel 11 on a fixed ring 8. The tube 16 is of square section to prevent it rotating relatively to the slide 15. The ring 8 is mounted on a frame 2, 3, attached to the pipe to be cut by a chain 6 and screw clamp. To the tube 14 is secured by clamp 27 a rod 26 mounted in ball or roller bearings 212 on the centre of a forked bracket 39 so that it is rotatable relatively thereto, the forked bracket being connected by ball or roller bearings 211 to a cross-head 21 which carries guide rollers 22 and is slidable on a bar 20 fixed to adjustable links 23 pivoted on axles 24 on pillars 25a, 25b, fixed on the frame 2, the links being approximately equal in length to the radius of the pipe 5. Alternatively the rod 26 may be fixed to the bracket 39 and journalled in the tube 14. Actuation of the ring 9 through the rod 26 moves the slide 21 along the bar 20 and raises and lowers the bar on the pivots 24 so as to follow the contour of the pipe. The links 23 are slotted and secured by clamp nuts 37 according to the diameter of the hole to be cut and the weight of the slide 21 &c. is partly counterbalanced by counterweights 30 carried by adjustable links 31. In order to cut offcentre holes in the pipe the ring 8 and parts mounted thereon may be adjustable laterally on the support 2 against a scale 34 and secured in position by studs and slots 40. For cutting irregular shapes in pipes the slide 15 is provided with a roller on a vertical spindle pressed by compression springs fitted over the bars 16 against a template fixed on vertical supports to the ring 8.