A welding assembly (1) for welding two rails (2) of a track includes two rail clamping units (5) movable towards one another in an assembly longitudinal direction (4). A power rail (10) provided for power transmission is configured as an assembly guide (3), extending in an assembly longitudinal direction (4), which is spaced from displacement drives (11) and connects both rail clamping units (5) to one another. The power rail (10) is equipped with a cooling device and displaceable in the assembly longitudinal direction (4) relative to the rail clamping unit (5) equipped with the power rail contacts (8).

A machining fixture for semi-automatically reconditioning an articulated connector is provided. The fixture comprises a housing having at least two side walls, a top plate having a first opening connecting the side walls, and a bottom plate connecting the side walls, the side walls, top plate, and bottom plate defining an interior space. The fixture also includes a clamping mechanism attached to at least one of the side walls, the clamping mechanism comprising a curved hook portion, the curved hook portion being laterally adjustable.

A post-heating treatment device includes a detecting device for a height variation of a surface of the rail at every, predetermined pitch along a length direction of the rail, a control unit for defining a position of the rail to be a starting point of the welded section when the height variation detected by the detecting device at every predetermined pitch exceeds a predetermined threshold for the number of a predetermined times consecutively and defining a position of the rail to be an end point of the welded section when the height variation detected by the detecting device at every predetermined pitch is below the predetermined threshold for the number of the predetermined times consecutively, and a heating unit for heat treatment based on a position of the welded section detected by the detecting device. A post-heating treatment method using the post-heating treatment device is provided.

The present invention relates in particular to a mold (M) for aluminothermic welding of a metal rail (1), which comprises at least two substantially identical pieces or shells (4), configured to be temporarily assembled opposite one another and on either side of said rail (1) to enclose the head (10), web (11) and foot (12) of this rail (1), each piece or shell (4) having an upper opening (43), which opens onto an internal cavity (44) bounded by walls (45, 46, 48) configured to enclose the head (10), the web (11) and the foot (12) of said rail (1), characterized by the fact that said internal cavity (44) comprises a compressible sealing coating (5) only against the walls (451, 46, 48) configured to enclose said web (11), foot (12) and underside of the head (10), with the exception of the rest of the head (10) and the underside of the foot (12).

Proposed are the welding conditions under which welds are always stably formed such that the difference in hardness between flash-butt welds and rail base metal and the deflection in a bending test are in better ranges. A plurality of pieces of rail base metal are joined via welds formed by flash-butt welding, where the rail base metal has a chemical composition containing C: 0.60 to 1.20 mass %, Si: 0.10 to 1.50 mass %, Mn: 0.10 to 1.50 mass %, and Cr: 0.10 to 1.50 mass %, with the balance being Fe and inevitable impurities, and the flash-butt welding is performed with an amount of welding heat input of 1.50×10.sup.5 kA.sup.2×sec or more and 4.50×10.sup.5 kA.sup.2×sec or less.

A welding unit for welding rails of a track has a unit lower edge forming a lower boundary of the welding unit, with regard to a vertical, and a shearing device provided for removing a weld bead. A rail base section of the shearing device is designed to be lowered, relative to the welding unit, by way of a drive from a rest position situated above the unit lower edge into a shearing position situated below the unit lower edge. Thus, the welding operation can be carried out without lifting the rails from the sleepers.

Apparatuses configured to be deployed from mobile welding repair vehicles for the repair of railroad trackwork allow a welding system to be stored and deployed from the mobile welding repair vehicles. The apparatuses deploy from the vehicles on a slide system and are supported by one or more legs, the system having 180-degree or greater rotation for full reach of railroad trackwork for welding repair thereof. Methods of using the same are further provided.

The present disclosure relates to the manufacturing of railway steel rail, and a post-weld heat treatment method for 1,300 MPa-level low-alloy heat-treated steel rail. The method comprises: (1) subjecting a steel rail welded joint having a residual temperature of 900-1,100° C. to a first stage cooling to lower the welded joint surface temperature to 650-720° C.; (2) subjecting the steel rail welded joint to a second stage cooling to lower the welded joint surface temperature to 480-550° C.; (3) subjecting the steel rail welded joint to a third stage cooling to lower the welded joint surface temperature to 10-30° C. The heat treatment takes advantage of the welding waste heat and does not require a reheating. The martensitic structure in the metallographic structure of the steel rail welded joint can be controlled to ≤1% and the fatigue life can reach 3 million times, which is conducive to operation safety of the railway.

A casting mold (6) consists of two mold halves (4, 5), which are intended for setting up on both sides of the welding groove (3) between two rail ends (1, 2) to be connected, thereby forming a casting space (8) representing a cross-sectional profile of the rails. For sealing the casting space (8) between the rail bodies on both sides of the welding groove (3) and the wall portions (9, 10) of the casting mold (6) that are facing this welding groove, inserted in gaps (11, 12) are strips consisting of a compound at least containing expandable graphite, which as a result of heat being supplied during a preheating process expands and forms a reliable seal. In comparison with using filler sand at this point, there is the advantage that a much smaller quantity of compound has to be carried along when working on the laid track.

A welding apparatus for welding rails of a track comprises two welding units which are movable relative to one another and which are each equipped with clamping jaws at a lower end. The clamping jaws are configured for resting on a web of the rail. Each welding unit is connected to a supporting device which can move relative to the welding unit and which is provided for resting on the track during operation.