The different welding procedures are distinguished by different preheating times, necessary portion weights and pouring techniques.
For special rail types special welding processes have been developed as well.
- SkV-F PROCESS
- SkV-L PROCESS
- SKS PROCESS
- SkV-M PROCESS
- SMW-F
- SOWOS
- SKV ELITE
- Composite Kits
Thermit® Welding is a potentially hazardous and skilled operation, which must not be undertaken by anyone who has not attended the appropriate training course. Detailed instructions for the installation of a Thermit® weld are available for each process, but they can be summarised as all having the following elements:
 A carefully prepared gap is produced between the two rails which must then be aligned using a straightedge designed to produce a slight lift at the rail joint. |
 Preformed sand moulds are supplied which locate around the prepared gap. These are fixed in position and sealed to the rail with a refractory material. A steel crucible is positioned above the moulds and the Thermit® powder is charged into it. The moulds and rail are then preheated by means of an oxy/fuel gas burner. |
 On completion of preheating, the burner is removed and the Thermit® powder is ignited. The exothermic reaction between the powder constituents produces the Thermit® steel, which is automatically discharged into the moulds to produce the weld. |
 After the molten steel has solidified, the equipment is removed, and the excess steel around the rail head removed by means of a hydraulic weld trimmer. When cool, all the remaining mould material is removed and the welded joint fastened down, after which the rail head is ground to profile. On completion of grinding, the joint is ready for service. |
