Patent GB-448416-A (GB)
Title: Improvements in or relating to the surface hardening of rails and to rails treated thereby
IPC: C21D9/04
Filed: 1934-08-27
Abstract: 448,416. Surface-hardening rails. OXWELD RAILROAD SERVICE CO., 230, North Michigan Boulevard, Chicago, U.S.A.-(Assignees of George, H. S.) Aug. 27, 1934, Nos. 24654, 24655, and 24656. Convention dates, Sept. 6, 1933. [Class 72] In the surface-hardening of the tread surfaces at the ends of rails in a section of track, by the application of a high temperature source of heat whose heating effect remains constant, the source of heat is applied to part of each of said areas for the same length of time in such manner that the heating stops short of the extreme rail corners, e.g. # in. to # in. from the ends of the rails, the said portions being heated to a temperature above the critical range and then being allowed to cool naturally. The source of heat may be oscillated during its application and may be applied so that at the boundary between the treated and untreated portions of the rail surface such area varies in width longitudinally of the area, e.g. said boundary may extend diagonally across the rail surface. When the worn ends of the rails are built up by depositing metal thereon, the heating extends to an area beyond that of the deposited metal. Both abutting ends of rails at a rail joint may be treated simultaneously by applying two sources of heat, one for each rail. When treating the rails, the sources of heat may be oscillated to heat up a small portion of the surface and then may be moved longitudinally while oscillating transversely to complete the heating. The rails may be treated in situ by mounting the sources of heat, preferably multi-flamed burners, on a carriage which is movably supported on the rails, the carriage being moved when the particular tread surface has been treated. The heating of the surfaces may be effected from the end of the rails inwards or from the central portion outwards towards the ends. When treating rails in situ by means of oxy-acetylene burners, the acetylene cylinders A and the oxygen cylinders O are mounted on the platform 31 of a truck T which is supported on wheels 27 which run on the rails 66 to be treated and the burner carriage is mounted on the ends of the truck T so as to be adjustable vertically. Acetylene gas from the cylinders A passes by pipes 44 to manifolds 45, through regulating valves 48 and flexible tubes 57 to the mixing chambers 59, the oxygen being supplied thereto by pipes 50, valves 51 and flexible tubes 58. The flow of acetylene and gas to the chambers 59 may be controlled by cut-out valves 52 which are operated by a lever 53. The mixture of acetylene and oxygen from the chambers 59 is delivered by pipes 62, 63 to the manifold blocks 64, each of which is provided with three transversely aligned nozzles 65. To prevent any back-firing, the nozzles may be provided with water-cooled jackets or a baffle 65a, Fig. 3, may be secured to the block 64 and mounted so as to extend between the nozzles 65. Pointers 74 are adjustably mounted on the manifolds for the purpose of aligning the burners on the rails and the gas issuing from the nozzles are ignited by pilot jets 67 mounted on an arm 68 connected to the manifold and fed by a pipe 72 connected to the acetylene supply pipes. To provide trapezoidal or triangular-shaped treated areas at the ends of the rails, the blowpipes B are moved longitudinally of the rails and simultaneously a transverse movement is imparted to the blowpipes B. The blowpipe carriages C are pivotally mounted between brackets 80, Fig. 5, which are welded to an inverted U-shaped frame 82 and in which the ends of a shaft 77 are journalled. The pivotal mounting of the carriages comprises two arms 84 pivotally connected at 85 to the outer ends of the brackets 80, the opposite ends of the arms being connected by a V-shaped member 86. A lead screw 88, for moving the carriages longitudinally of the rails is journalled in the ends of the arm 84 so that it lies within the member 86. The screw 88 is provided with a right and a left hand thread for the purpose of moving two carriages C in opposite directions, the carriages being moved by the engagement therewith of half-nuts 93 which are secured to the inner surface of a U-shaped block 95, Fig. 7, which is kept in contact with the member 86 by a block 99 held in place by a screw 101 and also by the engagement with the upper part of the member 86 of a groove 97 in the wall 96 of the block 95. The block 99 is also secured by a screw 105 to the block 103 which supports the chamber 59. To adjust the blowpipe B vertically, the pipe 63 of a blowpipe B is fitted in a member 117 provided with an opening in which fits a tube 115 welded to a plate 118 which slides in grooves in a projection 106 in the back of the block 95 and is adjustable by means of a screw 109, operated by a knob 111. To adjust the blowpipes transversely, the block 117 is moved by operating a knob 126, Fig. 5, on the end of a threaded stud 121 which also passes through a plate 123 mounted on the tube 115. To oscillate the blowpipes transversely of the rails, arms 128, Fig. 6, connecting the shaft 77 and the screw 88, are eccentrically mounted on the shaft 77 and thus on rotation of the latter the carriages C are rocked about the pivots 85 of the arm 84. To move the carriage on the screw 88, the latter is driven from a gear 133, Fig. 5, on the shaft 77 through an idler gear 134, Fig. 5, by a gear 135, the gear 134 being mounted on a stub shaft 139 which is secured in an arcuate arm 143 loosely mounted on the shaft 77 and provided with a handle 144, Fig. 4. The shaft 139 is so positioned that, when the handle 144 is moved to the down position, the gear 134 engages only the gear 133, but when moved to the up position the idler 134 engages both the gears 133, 135. The arm 143 is maintained in either of these positions by spring means. To move the blowpipes transversely and longitudinally simultaneously, e.g. in the production of a trapezoidal shaped treated area, a gear 155 on the shaft 77 engages a gear 156 on a shaft 158, Fig. 5, which is in two portions which can be connected by a clutch M, the portions of the shaft being mounted in bearings 159, 160 carried by plates 161, 162 secured to the righthand bracket 80 and the plate 82 respectively. The clutch is operated by a handle 167 which is forked to engage a grooved collar on the movable portions 165 of the clutch M. A bevel 173 on the outer end of this portion of the shaft engages a bevel 175 mounted on the end of a screw-threaded shaft 177 which passes through an opening in the side wall of the member 82, Fig. 7, and a threaded nut 181 formed integrally on a plate 182 on which the member 82 rests so that when the shaft 177 is rotated the member 82 and with it the blowpipe B are moved. To adjust the blowpipes longitudinally of the rails 66, a threaded projection 194 on the underside of the plate 182 is engaged by the screwed shaft 195 which passes through the wall 191 of a hollow block 190 on which the plate 182 rests, the shaft 195 being operated by a handle 197. In addition to the limited transverse adjustment by the knobs 126, the blowpipes may also be adjusted transversely by a hand wheel 204, Fig. 7, of a threaded shaft 203 which passes through a threaded lug 207 on a plate 201 which is provided with recesses into which fit undercut grooves 200 on the projections 199<1> on the block 190. To adjust the blowpipes vertically of the rails, a shaft 212, Fig. 3, provided with a handle 211 extends through a projection 213 on the plate 212 and also through a plate 215 integral with the latter. One of the bevelled edges 216, Fig. 5, of the plate 215 fits in an undercut groove 217 in a hollow block 218, the part 239 of which is secured to the frame of the truck T and the other edge 216 is kept in position by a bevelled strip 219 secured to the block 218. The outer end of the shaft 212 is provided with a bevel 224 which engages a bevel 228 mounted so as to be movable along a threaded rod 230 mounted in the recess 222 of the block 218, a projection 236 on the plate 215 being threaded to engage the rod 230 and also limiting the downward movement of the plate 215. In carrying out the heat treatment of the end surfaces of the rails, the blowpipes are moved into position over the rails by operating the handle 211 and then adjusted in position by turning the knobs 111 and 126. The blowpipes are then oscillated transversely over the first part of the rail surface by turning the shaft 77, the screw 88, the blowpipe and the carriage C being rocked about the pivots 85 by the eccentrically mounted arms 128. After the surface has been heated to the desired temperature above the critical range, e.g. 1600‹ F., the handle 144 is raised to connect the gears 133, 134, 135 and thus the shaft 77 and the screw 88 thus moving the blowpipes longitudinally and at the same time by actuating the clutch M to connect the two parts of the shaft 158 to move the blowpipes transversely. As the screw 88 is provided with right and left-hand threads, the two carriages C mounted thereon and operated by the nuts 93 will be moved in opposite directions and thus corresponding surfaces of the abutting ends of two rails will be treated. When the nozzles 65 of the burners of the blowpipes have moved off the edges of the rails, the valve 52 is closed and the rotation of the shaft 77 stopped. When the heat treatment has been completed the brakes on the truck T are released and the truck moved by hand or mechanically to the next rail joint of the section of the tracks to be treated.