Evaluation of rail head surface repair using SMAW process with pre heating condition

The railway maintenance industry has been using a welding process to repair the damage on the rail head surface due to its constant and continuous friction with train wheels. the damage area always reoccurs at the same location. a preheating condition has been set in this study to evaluate if it’s an improvement to the rail head surface. as preheating is a process that slow’s the cooling rate of the weld and the base material,resulting in softer weld metal and heat affected zone microstructures with a greater resistance to fabrication hydrogen cracking. the spectrometer and hardness test are applied in order to study driven changes in the microstructure and macrostructure of rail specimens at the rail head surface. it is shown that welded layers are clear from any defect due to the normal pressure with rapid change of temperature during usage and also surface oxidation. welded layer were free from any visible defect such as porosity and crack. © 2015,penerbit utm press. all rights reserved.