RAIL STRAIGHTENING METHOD, RAIL LENGTH STRAIGHTENING METHOD (2 VERSIONS), AND RAIL STRAIGHTENING MACHINE Russian patent published in 2003 - IPC

FIELD: railway transport. SUBSTANCE: according to proposed method of rail straightening in butt joint zone, rail sagging is determined and rails are subjected to cyclic bending by application of forces directed upwards by at least two times. Said forces are increased in each cycle, and after said bending of rails in vertical plane, rails are subjected to bending by forces directed downwards and residual sagging is eliminated by grinding. According to first version of rail length straightening in welded butt joint zones, first said sagging of rail length is decreased by preset value by changing direction of applied force to opposite one so that in process of completing cycle, force should be directed downwards, then rail length is subjected to bending by force directed upwards and residual is eliminated by grinding. According to second version, rail length is subjected to bending to provide arrangement of roll surface in butt joint zone by changing direction of application of force to opposite one so that in process of completing cycle force should be directed upwards. Then rail length is subjected to bending by force directed downwards, after which residual sagging is eliminated by grinding. Proposed device contains frame mounted on track machine, hydraulic cylinder secured on frame, three rail grips mounted on frame. One of grips, namely, middle one, is coupled with hydraulic cylinder, and it is furnished with rail grip turning hydraulic cylinder. Two other grips are spaced relative to middle grip along frame and are mounted at both sides. Fork for thrusting against rail at straightening is rigidly secured in lower part of said hydraulic cylinder. Guide is rigidly secured in upper part of said hydraulic cylinder, being hinge-coupled with rail grip turning hydraulic cylinder. One middle rail grip is hinge-secured on fork for thrusting against rail. EFFECT: increased capacity at alternating straightening of rails or rail lengths, enlarged elastic area, reduced residual stresses after straightening. 6 cl, 11 dwg