The invention of the Coldheat200 concerns a welding process for weld cladding of elastically supported or electrically insulated Vignole or grooved rails. During this process, the entire rail section that is meant to be provided with weld cladding is heated by the means of a magnetic field, generated by an induction cable that is placed on the rail.
With the known welding methods of such rails, the occurring temperatures are considerably higher than 200°C. With the invention of the Coldheat200, a defined heat and precise temperature monitoring is being utilised. Existing materials are not damaged, defects and wear and tear of the rails can thus be eliminated and their life cycle extended – regardless of the type of system installed and even applicable to city railway tracks without any problems.
A constant rail temperature over the entire length of the section that needs to be welded is achieved by lifting the longitudinal inductors from the rail at the start of the welding process and placing them back on the rail after the welding process is completed.
The course of the welding process is being documented by the means of an on-board computer with all its parameters (welding speed, wire feed, power, voltage) – before, during and after the welding process. Thus, the welding process can be traced and the procedure can be repeated at any time, furthermore a constant quality is guaranteed.
The device for carrying out the welding process is adjustable and is arranged transversely to the rail that needs to be provided with weld cladding. Due to the telescopic adjustment possibility, the width of the device can be adapted to the gauge of the track formed by the rail to be welded on, for example to a track dimension of 1000mm to 1500mm.
The gear of the Coldheat200 consists of six wheels, which are individually suspended and electrically insulated from each other. Therefore, there is no electrical connection between the wheels on either side. At least one of the wheels, which are placed on the rail that needs to be welded, is connected to a drive unit. The wheels can be moved on the rail head and are kept in the correct track by guide drifts, which are arranged inside the groove. This enables the Coldheat200 to travel accurately through the track without constraints, even on curved rails.