Patent GB-291723-A (GB)
Title: Improvements in and relating to welding of rails
IPC: E01B11/50
Filed: 1928-06-05
Abstract: 291,723. Stedefeld, C. June 3, 1927, [Convention date]. Welding railway and tramway rails; welded joints. --In an apparatus for repairing or renewing rails in gapless welded rail tracks the welding transformer and the devices for gripping, guiding, moving, and supplying current to the rail ends are mounted on a portable frame, symmetrically arranged with respect to the rail. The fixed rail is secured in the frame 13 by jaws operated through screws and worm gear 33 by hand wheels 32, and the movable rail 22 is provided with plates and is operated by rollers 20 on a lever 19, being guided through rollers eccentrically mounted in the frame and adjusted by hand levers 29, which are held in adjusted position by lock levers and toothed segments. The to and fro motion given to the rail during the preliminary heating or burning-off of the rail ends is effected by a small double-acting hydraulically operated piston 17 linked to the lever 19 and the final movement to complete the weld is effected by a large single-acting hydraulically operated piston 101 having a pressure plate 25 to engage the lever. The contact jaws 41, 42, Fig. 6, are independent of the clamping jaws, are shaped to fit the fish-plate groove in the rails and are mounted on pivoted arms 43, 44 adjusted by a right and left hand screw 46. The contact jaws are arranged as far as possible from the joint to obtain a uniform heating effect and may be further from the joint than the clamps. The transformer 14 is connected to the movable contact jaws by a bundle of flexible copper bows 50 and to the fixed jaws by flexible copper bands. In cases where a piece is first cut out of the rail and a piece longer than the gap produced, to provide for the burning-off and butting, is first welded to one rail end and then to the other, the first weld is effected without lateral deflection of the rail. The amount of metal to be burned off is measured by a scale 52, Fig. 7, index 53, connecting rod 54 and counter bearing 55 secured to the hinge pins 51 of the arms 43, 44. The rail ends are brought into contact and the index then set forward by the amount the rail is too long and welding then effected. A separate index may be used for the burning-off and butting limits. The lateral deflecting means is put out of action when the first weld is being effected. In the form shown in Fig. 8, when the hand lever 61 and thus the control pistons 62, 63, 64 are moved in the direction of the arrow, fluid passes from the inlet 56 through chambers 57, 58, ports 65, chamber 66 and pipe 67 into the cylinder end 68 to operate the lever 19 and thence passes through pipe 69 containing a throttle valve 71 into the end 70 of the deflecting cylinder. Exhaust from the) cylinder end 72 passes through pipe 73, non-return valve 74, three way cock 82, and pipe 75, into the chamber 76, whence it passes through ports in the control sleeve to the exhaust pipe 79. Exhaust from the cylinder end 80 passes to the exhaust pipe 79 through pipe 81 and three way cock 82. When the lever 61 is moved to its other extreme position fluid passes through control sleeve and pipe 81 into the end 80 of the deflecting cylinder and then through pipe 84 containing throttle valve. 85, and through pipe 73 to the cylinder end 72. Exhaust from cylinder end 68 passes to the exhaust 79 through pipes 67, chambers 86, 87 and pipe 88, and from the cylinder end 70 through pipes 69, 89, and non return valve 90. After preliminary heating is effected the piston 101 is put in operation to complete the weld. For this purpose a valve 60 is opened and a valve 94 closed by a lever 93 operated by a rod 92 from an angle lever 91 so that when the lever 61 is again moved in the direction of the arrow fluid also passes by way of pipe 59, chambers 95 ,96 and pipe 100 for the cylinder 97. The control rod has. a piston 102 of larger diameter than the piston 62 so that the operator feels a pressure at the hand lever proportional to the battery pressure. An overflow container 103 is provided to allow for the pumping action produced by the difference in diameters of the pistons 62, 102. Exhaust from the cylinder 97 when the lever 61 is returned is effected through chambers 99, 77, 78. If no lateral deflection is required the deflecting cylinder is. cut out by reversing the three-way cock 82 and closing the valves 105 and 106. The welding-apparatus 107, Fig. 9, may be universally jointed at 108 to the end of a crane arm 109 which may be raised on a pivot 110 by a screw 111 to the position 109<1>, the arm being mounted on a turn table 116 carried by a wagon 118 movable on one pair of rails so that the welding apparatus may reach any of the rails of a double track. The turn table may have a super structure 119 and may contain devices for grinding the joint and heating furnaces for fining the grain of the weld. which may be attached to the arm on removal of the welding apparatus. It may also contain a generator 120 such as a Diesel engine and dynamo, which may be arranged on the turntable or on an extension of the crane arm to act as a counterweight. When used on a suspended mono-rail track 121, 122, Fig. 11, supported by arms 123, 124 on the main carriers 125, 126 of a structure resting on supports 128, the welding-apparatus 107 with operators' platform 137 is suspended by ropes or chains from the traveller 133 of a rotary pillar crane 132, which is mounted on a wagon 131 travelling on auxiliary rails 129, 130 on the carriers 125, 126. To free the rail sections 121, 122 for the passage of traffic, the welding apparatus is provided with rollers 139 so that it may be drawn up on to the wagon 131, pivoted guide members 140 being provided so as to avoid contact with conductor rails 138. Specification 282,806 is referred to.