DR800 flash-butt welding container for railway construction     

This specification describes a self-contained fully enclosed, ready for service,in-track welding system. The system is designed for tunnel operation and plain line.The unit is designed to run with high flash point fluids and all cables and hoses arefitted with fire proof shields. The system is complete with a diesel engine generatorset and integral cooling system. Voltage control is by means of direct control.

Hydraulic power is derived from a hydraulic pump driven from a 30kW electricalmotor. The electrically driven pump provides power for both the welder and thecrane. A 21 kW chiller, complete with circulating pumps, is provided to ensure the welding head operates within the correct temperature levels. This cooler is electrically driven from the generator secondary circuit.

All operating components are mounted on a steel base and are enclosed withi a fire proof lined aluminum enclosure. Design of the enclosure and base allows the unit to be mounted from static plant welding or to be mounted directly on a truck chassis for mobile operations.

Range of application

    For welding of different rail types, only the initial settings are needed to be made and once they have been made, the machine can weld the same rail type without other subsequent settings.

Production capacity (thermal capacity)   

    For profile UIC 60, burr removal included,      up to10 welds / h

1. DR Welding Head

The main features of the DR800 welding head are the following:

The welding head DR800 can weld both vignole and grooved rail (it needs specific electrodes and shearing knife for required rail type) and can be easily converted.

The machine DR800 is designed for flash-butt welding by continuous flashing of rails with cross-section area from 6.400 mm2 up to 10.000 mm2 with flash removing immediately after welding under field conditions being a part of movable rail-welding plants.

The welder ensures high efficiency and welding quality. Its compact and relatively light design allows using any vehicle, placing the welder on the welded rail joint and quickly adjusting weldin parameters.

Alignment between the two rail ends is carried out in two planes: Vertically onto crown stops,horizontally on the center of the rail web.

2.Shearing Knife

   Full profile shearing shall be achieved by passing the shear tooling across the weld immediately after the weld is made. The cutting edge is build-up by hard facing electrode for high temperature working conditions 850 °C.

3.Welding Electrodes

     Contact with the rail web is by special material electrodes. The electrodes are made by forged high quality alloy with good electrical conductibility and hardness 220 HB.

     These are specially designed with spring loaded location points to ensure accurate alignment of the rail ends for welding.

4. Control and Power Cabinet

    All welding machine related control elements are housed in a control cabinet. 

    The cabinet is intended for a sheltered installation (0°C to + 55°C) equipped with its own air conditioner unit, and heat insulating foam.

     Automatic programmable microprocessor-based system is designed for control of actuators and mechanisms of mobile welding machine GT100 for butt induction rail welding.

    The system controls all aspects of the welding cycle including the final shear. Specific welding schedules are available for most rail sections and can be developed for any special requests. 

Weld time is typically 2.5 to 3 minutes with approximately 25 – 38 mm of rail consumption.

Welding voltages are varied according to the rail size and according to the welding program.

These voltages are provided by a powerful thyro control and are in the range of:

-      Stage I and II 400-440 V

-     Stage III 300-340 V

5. WPC 2.0 (Welding Process Controller)

The Welding Process Controller(WPC) gives information about the following parametersof the welding process:

-       the effective size of voltage in the welding transformer (V)

-       the effective value of current in the welding transformer (kA)

-       the forging force - the force of pressing together the rails to be weld (kN)

-       the displacement of the welding jaws (mm)

-       the time elapsed during the welding process (s 

-      the temperature of the environment during the welding process (°C)

-      the GPS position of the welding machine during the welding process

    Welding Process Controller(WPC 2.0) is used for recording data during the welding operation of the Flash-Butt welding Machines, the data will be processed and displayed in real time under a simplified graphical on a touch screen display and stored on a flash memory card (CF) for further processing in a complex graphical on a personal computer (PC).

6.Hydraulic Power Unit

    Hydraulic system consists of an electrically driven power unit, required valves, hoses/piping, controls, etc. to operate the welding system, crane and optional control/feed circuits.

     Hydraulic power unit is electrically driven Kawasaki variable displacement pump for main hydraulic system and a Sauer Danfoss gear pump for crane control.

     Additionally an emergency pump is mounted on the Hydraulic power unit in order to provide hydraulic power to the welding head and crane in case of main power supply fails - gen-set failure. This pump   is a gear type pump, 9 l/minute flow and is driven by 3 kW electrical motor which can be connected to any external portable gen-set

Hydraulic power unit furnishes: at 400V, 50HZ:

    100 l/minute at 240 bar for welding head circuit

    25 l/minute at 160 bar for crane circuit

    9 l/minute at 160 bar emergency circuit for welding head and crane

    25 l/minute at 10 bar for cooling/filtration circuit

7. Cooling Unit

     A cooling unit is provided to ensure the welding head operating temperatures are maintained within pre-set limits.

    This is the most economic configuration, which is obtained by calibrating the finned heat exchanger banks to allow proper operation of the refrigerator at external air temperatures not exceeding 55°C.

 9.Crane

A self-contained articulating twin boom hydraulic crane is provided to handle the

welding head.

The crane is designed for a lift capacity of 4000 Kg at an outreach of 3.6

meters.

This slewing crane has a pivot capability of 75 degrees either side of the center

to allow welding of adjacent rails. These pivot capabilities together with its extendible

arm function assures a large covering area for the welding head.

When the crane is retracted into its transit position, it is designed to ensure a

secure unit for travel.

The crane is fitted with a radio remote control for motion control.

Power for crane is provided by a hydraulic pump which operates on 160 bar.

Crane function:

- Lift: Up / Down

- Extend: Out / In

- Rotate: Left / Right

These are controlled electrically by the Remote Control and manual mode by

using levers located on the top of crane.

10.Weatherproof Container

The welding equipment is housed in a weather-proof container with the chassis

and basic framework constructed from welded structural steel. The container body is

made of fabricated aluminum empowering total protection with minimal weight.

The bodywork incorporates ventilation grilles, removable panels for service and

maintenance, personnel doors and clear access to the handling equipment for the

flash-butt welding operation.

Container unit is fitted with built-in lifting eyes to allow for multiple lifts with

proper lifting spreader beam when moving from site to site.

The generating set is separately compartmented being sound-proof and heat

insulated.

The container is fitted with standard corner castings mounted at distances same

as for a standard 20ft container, thus can be mounted on any platform fitted with

standard twist-locks same as for any standard shipping container.

Dimensions of the Container Body:

• • Height: 2565 mm
  • Length: 7560 mm
  • Width: 2555 mm

Standard color is white, but at customer request can be chosen any RAL code.

11.Accessories

 Air compressor

A Kaeser compressor, model Classic 320/90 W will be fitted inside the container for cleaning and maintenance purpose