Thermit welding processes
Thermit welding processes

Thermit® welding processes incl. all consumables

With the Thermit® welding processes nearly all rails of various profiles and grades worldwide can be continuously welded. Thermit® consists of aluminum granulate and iron oxide which after igniting exhibits a strong exothermal reaction. The extreme reaction heat of is able to create liquid steel up to 3000 °C without an auxiliary energy source and therefore to weld the ends of rails. Using this process we guarantee you the safe joining of rails in heavy haul and high speed networks while at the same time increasing travel comfort and the lifetime of the rails.

As an end-to-end supplier of aluminothermic welding we develop, manufacture and supply all components required for our Thermit® welding processes. Among the main components are:

  • Welding compound (Thermit® portions)
  • Refractory molds
  • Crucibles
  • Tools and machines used to carry out the work

We offer the following processes and components:

SkV-Elite L25 - Thermit® welding process

SkV-Elite L25 - Thermit® welding process

Quick welding process for flat bottom rails

Benefits

  • Short execution times and highly reliable
  • Economical thanks to the use of uniform mold shoes for all profiles and reduced gas consumption with short pre-heating
  • Process safety thanks to extensive expertise with the SkV welding process and its development
  • Highly adoptable as portions and moulds are available for most rail profiles and grades
  • Easy, quick and robust execution in track

 

 

Features

  • Standard gap width 25 mm ± 2 mm
  • Standardized preheating time of 2 minutes for profile sizes from 46E2 (U33) up to 60E1
  • One size of mould shoes fits all profiles
  • All crucible models may be used
  • Certified according to EN 14730-1

SoW-5 - Thermit® welding process

SoW-5 - Thermit® welding process

Quick welding process for flat bottom rails

Benefits

  • Economical thanks to small portion size and the use of uniform equipment for all profiles
  • Long life cycle of rolling surface because of short preheating times, resulting in small heat affected zones
  • Portions for all rail profiles and grades available
  • Result: Low life cycle costs
  • Easy, safe and robust execution in track

Features

  • Standard gap width 29 mm ± 2 mm
  • For gap widths of 40-50 mm and 65-75 mm available
  • All crucible models can be used
  • Certified according to EN 14730-1
  • Homologated in the Netherlands (ProRail), Denmark (Banedanmark), France (SNCF), Switzerland (SBB), Belgium (Infrarail) and many more

Head Repair Weld - Thermit® repair welding

Head Repair Weld - Thermit® repair welding

Full Head Repair 

In this process the complete rail head is ground out to remove deep kidney shaped defects and transverse defects.

Partial Head Repair

In this process only a part of the rail head is cut out to remove surface defects or wheel burns.

Benefits

  • Considerable reduction of maintenance costs through removal of local limited rail defects
  • Cost-intensive replacement of rails unnecessary
  • High quality alternative to conventional electrical contract welding
  • Re-setting of rail neutral temperature unnecessary
  • Cutting out a section of rail and re-alignment of rails is unnecessary
  • Available for all common rail profiles and surface qualities
  • Reduction of life cycle costs
  • Easy, safe and robust implementation on the rail
  • Only minimal additional training required for trained Thermit welders
  • Standard equipment
  • High quality through very high process reliability

Features

Cost effective alternative for a quick and economic repair of local limited rail defects of flat bottom rails such as squats, shelling, wheel burns or individual electrical welding defects. The result: you save the considerably higher cost of having to fit a replacement rail – and also significantly and sustainably reduce the life cycle costs of your rails. Our professional repair welding process Thermit® Head Repair is available for all common rail profiles and rail grades.

HPW - High Performance Weld

HPW - High Performance Weld

Quick welding process for flat-bottom rails

Benefits

  • New and innovative welding process using a special alloying concept
  • Unique, simplified and cost-saving logistics for the user
  • Applicable for all standard rail profiles and rail grades
  • Recommended welding process for heavy haul
  • Easy, safe and robust execution in track

Features

  • Optimized mechanical properties thanks to the special alloying system
  • Applicable only for gap widths of 29 ± 1 mm
  • Specially marked plug with container system currently available for three different hardness levels (350 HB, 370 HB, 400 HB)
  • Sand sealing using the Single Use Crucible I
  • Used in Europe on the Iron Ore Line (heavy haul railway in Sweden/Norway), as well as on other heavy haul railways worldwide

SRZ – Thermit® welding process

SRZ – Thermit® welding process

Quick welding process for grooved rails

Benefits

  • Largely user-independent compared to arc welding
    • This results in higher execution reliability
    • And this leads to high operational track reliability
  • Economical thanks to low life cycle costs
  • Welding of transitions with flat-bottom rail/ grooved rail possible using SRZ L50 welding process

Features

  • Standard gap width 25 ± 1 mm
  • Gap widths of 65-75 mm feasible using the SRZ L75 process
  • Sand and paste luting possible
  • All crucible models can be used
  • Applied the world over at all major and small municipal transport services

SKS - Thermit® welding process

SKS - Thermit® welding process

Quick welding process for crane rails

Benefits

  • Quick implementation possible even at great heights and despite limited space and work area
  • Can be applied on all crane rails including profile A150
  • Modifications for other big-profile cross sections on demand
  • Largely user-independent and semi-automated compared to arc welding
  • Easy, safe and robust execution in track

Features

  • Standard gap widths 23 ± 1 mm and 25 ± 1 mm (depending on profile)
  • Pre-heating times dependent on profile
  • Sand sealing using the Single Use Crucible I
  • Process is executed with 3-part molds as supported joint
  • Applied nationally and internationally on tracks and industrial companies’ sites

Long-life crucible

Long-life crucible

Multiple-use crucible for Thermit® welds

Benefits

  • Years of success with this proven long-life crucible system
  • Universally applicable, as all portion sizes can be welded
  • All components of the long-life crucible system can be ordered separately
  • Highly economical thanks to multiple use

Features

  • Crucible needs to be cleaned after an average of 15 castings
  • Up to 25 castings can be performed with one lining before this has to be replaced (depending on the portion size used / welding process)
  • For welding wide gaps (L75) a higher crucible extension ring is offered in order to increase the volume of the crucible
  • Contains an automatic tapping thimble

Single use crucible

Single use crucible

Single use crucible for Thermit® welds

Benefits

  • Optimization of operational procedures due to less weight and easier handling compared with long-life crucible
  • Applicable for all rail profiles and grades
  • Crucibles can be used for the disposal of welding residues after welding is completed
  • Reduced likelihood of welding errors because – unlike with long-life crucibles – there is no need to dry and to prepare the crucible before use

Features

  • Single use
  • The base incorporates a device for automatic tapping
  • Charged or uncharged available
  • Standard and wide-gap welds possible
  • Use for work in tunnels with appropriate filter attachment
  • Portion and crucible lining are protected against humidity

Service

Are you interested in our range of products and services or have questions? Please contact us. We will be glad to help you.