Welding and Track Maintenance Equipment

Flash Butt Welding

To complement our aluminothermic welding solutions in India, Pandrol offers a complete mobile flash butt welding plant hire service for rail companies. The service involves providing access to a flash butt welding machine, along with a trained team of operators to carry out the welding process to a high standard. There are four machines available for hire:

  • Two Paton International machines (K-920 and K-900) – both designed for welding using continuous or pulsed flashing, with burr removal immediately after welding.
  • A Holland H-1000 — a 100 tonne machine with capacity for handling the longest rail strings.
  • A Contrail CR-80 – a compact, versatile machine, with the welding of grooved rails a standard feature.

The mobile machines can travel on rail and road, so can be moved easily between job sites. All have been approved by the Research Designs and Standards Organisation (RDSO), Ministry of Railways, Government of India.

Технические особенности

  • In flash butt welding, the energy to join components is primarily provided by resistance heat from the parts themselves. The pieces of metal to be welded are separated and a current is applied to them. The gap between the two pieces of metal creates resistance and produces an arc to melt the metal. The time that the arc is present is the ‘flash time’.
  • The pieces of melted metal to be joined are pressed together under high pressure, causing the ends to join. No filler metals are needed.
  • An electronic control system is designed to provide a stable welding process according to pre-set parameters.
  • Flash butt welding machines use a clamping system of two horizontal mounted cylinders that clamp the rails with high force to ensure they do not slip during welding and upsetting.
  • The welding head is able to achieve 100T pulling force. It completes a welding cycle from aligning to flash removal in one automatic sequence. A flash removal device is integrated with the welding head.
  • Flash butt welding machines can be used either on or off track and can weld rails with a cross-section up to 12,000mm2.

Преимущества

  • Flash butt welding covers the whole welding cycle: preheat, pre-flash, steady flash, boost, upset, forging, and removal of flash material.
  • It creates rail that is much smoother than mechanically-joined rail because there are no gaps between sections. As a result of the lack of joins, the welded section has the same properties as the rest of the rail. This minimises uneven wear and tear on the rail, reducing inspection and maintenance costs and saving time.
  • The electronic control system provides a stable welding process and results in high-quality welding joints.
  • The welding head is designed to provide the highest standard in quality and tolerances of rail welding in-track and stationary conditions.
  • Flash butt welding is versatile – it can be used to make long welded rails (LWRs) and to convert short rails or LWRs into continuous welded rails (CWRs).
  • The flash butt welding machines are mobile – they can be driven to site by road or rail, saving time and making welding more efficient.
Welding and Track Maintenance Equipment

Flash Butt Welding