ALUMINOTHERMY. THE UNIQUE TECHNOLOGY
High-Speed Trunk Railroads in Progress
One of the general trends throughout National Railways worldwide is, now, the development of high-speed trunk roads. The attaining of this task has put forward new requirements as to the permanent way - that is, the need for elimination of bolted rail joints along the entire length of the way, including railroad switches.
Aluminothermic Welding (ALTW) has turned out to be excellently fit for these purposes - as the most effective, reliable and omnibus technique of rail splicing.
In 1859, the Russian chemist N.N.Beketov discovered the aluminothermy, which is the reaction of metals oxides reduction by aluminum. At that, plenty of heat is generated (to of up to 3000oC) within a short time interval and the molten metal originates.
The ALTW (by the intermediate casting method) of railway rails is allowed to be made in respect of
Aluminothermic rail welding is designed for both brand new rails and used ones.The technological process developed by SNAGA Co. takes account of the actual conditions of the rails to be welded operation: their profile, category, climatic effect, economic factors with regard to the welding process time limits (usually, a short 'gap' in train schedule), and the chemical composition of the rail metal.The welded rail joints made by the SNAGA technology are reliable in sharp continental climate of Siberia (with the ambient to ranging from -58oC to +59oC). Apart from railways, the welding is also applied on the municipal tramways.
The long ALTW-joints service experience shows that the nature and intensity of the change in the joint geometry parameters observed in the area of the dynamic action by the rolling stock on the joint corresponds to the nature and intensity of the change in the geometric parameters of the adjoining rails