GB808709A - Improvements in or relating to flame cutting apparatus - Google Patents

Abstract

808,709. Cutting by fusion. GROVE VALVE & REGULATOR CO. May 8, 1956 [June 13, 1955], No. 14277/56. Class 83 (4). A flame cutting apparatus for cutting holes in metal valve bodies 74 such as those described in Specification 808,708 comprises a frame 10, 11 adapted to be adjustably seated upon one horizontal side 73 of the body and carrying a vertical shaft 38 supporting a flame cutting torch 23 mounted for rotation about the axis of the shaft. The frame carries flanged wheels 14, Fig. 2, mounted on screw threads 18 on shafts 12 which are rotated by handles 19 for moving the wheels 14 inwardly to clamp the frame on the valve body 74. The shaft 38 is fixed to a cross member 22 of the frame and has rotatably mounted thereon a hub 39, Fig. 8 (not shown), from which extends an arm 41 carrying segments 44, 46 with arcuate slots 49, 52. The torch 23 which makes vertical cuts is adjustably mounted, Fig. 5 (not shown), on the end of an arm 36 pivoted at 43 to the arm 41 and adjustably clamped at 51 in groove 52. A second burner 24 for bevelling the cut edges is adjustably mounted, Fig. 6 (not shown), on a second arm 37 pivoted at 42 to arm 41 and adjustably clamped at 48 in groove 49. Segment 44 is rigidly secured to arm 41 whereby the bevelling burner 24 moves in a circular path only. Segment 46, however, is pivotally mounted at 43 to arm 41 and has an extension 54 carrying a cam roller 57 adapted to co-operate with a cam 56 fixed to the shaft 38. The profile of the cam 56 thus determines the path taken by the cutting torch 23 which path may be elliptical to compensate for distortions due to heating and cooling of the valve body. Springs 61, 62 press the roller 57 into engagement with the cam. The hub 39 is rotated on the shaft 38 by an electric motor 67 and tooth gearing 68, 69. A lifting ring 71 enables the apparatus to be moved to and away from the valve body. In operation the cutting apparatus is located on the valve body to be cut by a pin 77 extending through the shaft 38 and is clamped thereon by the wheels 14. The torch 23 is then moved inwardly of the cutting circle by a setting cam 64, Fig. 1, and after igniting the torch the motor 67 is started and the cam 64 is turned to bring the torch into the correct cutting path then determined by the profile of cam 56. After cutting the upper side of the valve body, the torch 23 is lowered through the cut hole, Fig. 5 (not shown), to cut the lower side of the body. The bevelling torch 24 is then used to bevel the cut edges, Fig. 6 (not shown).