Abstract: A welding unit for welding rails of a track includes a first sub-unit which is displaceable on unit guides in a rail longitudinal direction relative to a second sub-unit by using displacement cylinders. Each sub-unit includes clamping cylinders disposed underneath the unit guides and coupled to clamping jaws for clamping the rails. The two sub-units are connected by the displacement cylinders in that a cylinder body of the respective displacement cylinder is connected to one sub-unit and a piston rod of the respective displacement cylinder is connected to the other sub-unit. Thus, it is not necessary to support the displacement cylinders relative to a transverse beam disposed at the front.

Abstract: The invention relates to an energy supply system for a mobile resistance welding machine for flash-butt welding of track rails, comprising a combustion engine (1) coupled to a generator (2) as well as a charging device (5) for charging an energy store (7), wherein the energy store (7) is a buffer element of an intermediate circuit (13) to which a welding inverter (14) is connected. In this, the energy supply system comprises an island grid to which the generator (2) is connected and which is coupled to the intermediate circuit (13) by a controlled power converter (16).

Abstract: Provided in a tamping unit for tamping a track are squeezing drives (14) for a squeezing motion of tamping tines. In a hydraulic cylinder (19)—having a squeezing piston (17) with a piston rod (18)—of the squeezing drive (14), a first pressure chamber (20) for producing the squeezing motion (8) is provided. Additionally arranged is a second pressure chamber (21) for producing an opening motion directed opposite to the squeezing motion, and a third pressure chamber (22) provided for producing vibrations.

Abstract: The invention relates to an energy supply system for a mobile resistance welding machine for flash-butt welding of track rails, comprising a combustion engine (1) coupled to a generator (2) as well as a charging device (5) for charging an energy store (7), wherein the energy store (7) is a buffer element of an intermediate circuit (13) to which a welding inverter (14) is connected. In this, the energy supply system comprises an island grid to which the generator (2) is connected and which is coupled to the intermediate circuit (13) by means of a controlled power converter (16).

Abstract: Provided in a tamping unit for tamping a track are squeezing drives (14) for a squeezing motion of tamping tines. In a hydraulic cylinder (19)—having a squeezing piston (17) with a piston rod (18)—of the squeezing drive (14), a first pressure chamber (20) for producing the squeezing motion (8) is provided. Additionally arranged is a second pressure chamber (21) for producing an opening motion directed opposite to the squeezing motion, and a third pressure chamber (22) provided for producing vibrations.

Abstract: A welding unit for connecting two rails of a track by flash-butt welding, includes clamping jaws having contact surfaces intended for application to a rail web and a power jaw for current transmission having a contact surface for application to the rail web. The power jaw is displaceable relative to the clamping jaw in a pressing direction leading to contact with the rail. In an inoperative position spaced from the rail web, the power jaw, due to the pressure of a pressure spring, is situated in a forward end position with regard to the pressing direction, in which the contact surface of the power jaw projects beyond the contact surface of the clamping jaw.