Flame cutting and welding cannot be undertaken on rails coated with Alphatek, until the coating is fully removed around the portion of rail on which the weld is to be installed.
Alphatek is regularly used to coat rails and consequently prevents corrosion in high moisture areas. Examples of said areas include tunnels and underpasses ,as well as coastal areas and level crossings.
Corroded track is not suitable for a train to run across,and leads to the need for rail replacement. This gives precedent for the requirement of Alphatek coatings.
Track may at some point require a weld or flame cutting to take place but coatings prevent this from happening. This means that the rail coating must be removed for aluminothermic welding or flame cutting to progress. Themit provides a removal method for Alphatek to allow for the weld or cut to proceed.
The primary Thermit method of Alphatek removal includes a process on stripping the coating from the rail through the use of a sodium hydroxide solution. This is a cost effective and time efficient method, therefore allowing for a quick turnaround. This means preparation before an aluminothermic weld is as minimal as possible. This is a preferable method to mechanical methods, as mechanical methods are less effective ,more time intensive, and can potentially damage the rail.
Rails require thorough inspection before aluminothermic welding can proceed. The successful removal of Alphatek should be confirmed through a process of brushing the required rail section with a copper sulphate solution, due to its reactivity with the coating.