Aluminothermic welding 2018-04-11T15:31:02+02:00

Aluminothermic welding


The T3 one shot crucible

An outstanding and groundbreaking Railtech Deutschland innovation was the development of a disposable crucible with an integrated portion and tapping system, for quick and simple production of reproducible welding applications. Until the advent of this innovation, aluminothermic weld portions were mainly cast in what are known as long life crucibles, whereby the aluminothermic portions and the tapping system (thimble) were manufactured as standalone components. Our innovation greatly improved and simplified the process in terms of user friendliness, quality and work safety and has enabled our company to sell its products in all key markets worldwide.

Use and cost effectiveness

Welding preparation and the welding process itself take only a minimal amount of time.Simple and rapid disposal, because the fireproof inner crucible disintegrates.Thanks to intelligently scaled portion sizes, a broad spectrum of possible profiles can be covered with a relatively small inventory.No supplemental portion is needed for large gaps (L50, L70).Outstanding process stability reduces error rates, thus minimizing possible repair expenditures.

                                          T3.P                                                                                                                 T3.M



 Technical data

Our one shot disposable is ready to use without any preparatory steps; nor does it need to be filled with portions.The factory-installed tapping thimble minimize process errors of the type that occur with manual use of long life crucibles, plus anomalies such as freezing and delayed opening.The defined crucible profile allows for smooth and continuous reaction sequences.The crucible cover is built in such a way as to prevent reaction-mass leakage.The centered position of the disposable crucible encloses the welding-form inlet area.The short drop height of the molten steel helps to prevent impurities from being incorporated into the welding material.The generously proportioned outer jacket mitigates direct external impacts and protects the fireproof crucible from damage.The weatherproof packaging remains in place until the product is used



The T3 is also available with our STARTWEL® starter system

Welding mould SP.2P

SkV Premium: The new optimized welding process featuring rapid preheating

The standard, and highly reliable, SkV process for railroad aluminothermic welding, which has been in use for decades, has been substantially improved.

Thanks to the use of larger portions and more efficient preheating, the time needed to carry out aluminothermic welds has been reduced to a minimum.

Thanks to an optimized analysis method for SkV Premium portions (e.g. lower silicon content) and improved internal form geometry and robustness, we have significantly improved the process in terms of melting, shearing performance and mechanical/technological properties. In the interest of improving welding ergonomics, our crucibles are now around 1.5 kilograms lighter, but are still extremely safe to use.

SP variant

Apart from the SkV Premium solution, we also offer the SP variant for this process. By virtue of their external geometry, these forms are slimmer and lighter and can be sealed with either sand or paste.

Metallurgical properties

Identical metallurgical micro-structure

  • Only a small heat affected zone (HAZ)
  • Homogeneous fusion zone
  • Low internal stress thanks to homogeneous elimination of heat centers
  • Rated for all steel qualities

Rectangular riser section

Process characteristics

  • Preheating time only 90-120 seconds.
  • For the same track profile, all SkV-P and SP welding parameters such as orientation,  preheating and shearing time are identical.
  • Rectangular riser geometry with adequate width makes it easier to center the forms; plus it’s possible to verify at any time that the forms are in the correct position.
  • Thanks to the use of special binders and additives, the high-quality form sand eases the task of working on contours, and ensures high stability for robust worksite use.

Paste allows for avoidance of the following welding anomalies:

  • Gas bubbles owing to unduly damp sand
  • Sand inclusions
  • Bubbles from sand inclusions
  • Pores on weld collar
  • Leakage owing to unduly dry sand

Paste or sand?

Paste allows for avoidance of the following welding anomalies:

  • Gas bubbles owing to unduly damp sand
  • Sand inclusions
  • Bubbles from sand inclusions
  • Pores on weld collar
  • Leakage owing to unduly dry sand

VGR and CGR shearing devices


  • Compatible with all Vignol and grooved rails
  • Head width: less than 115 mm
  • Weight: 33 kg
  • Two locking levers each
    for Vignol and grooved rails


  • Compatible with all crane and grooved rails
  • Head width: less than 135 mm
  • Weight: 39 kg
  • Four locking levers
    with a range of positions

Railtech Deutschland GmbH has developed a new generation of shearing devices that allow for aluminothermic welding of all types of rails. With this system, excess weld collar can be removed simply and extremely safely. We have optimized the weight of the robust steel frames so as to render the device user friendly and compact, while still retaining its stability and durability.