A fillet weld in steel structures of railway bridges is a weld that joins two pieces of metal at right angles. The air-cooled induction heating machine can work in the field without water cooling, preheating the fillet weld to 120°C without contact.
Since the induction heating process does not burn fuel, no moisture is present during welding. This significantly reduces the risk of hydrogen-induced cracking and minimizes the risk of cold cracks in the weld. Due to the small heat loss of electromagnetic induction heating, the corner joints of steel structures of railway bridges can obtain better weld penetration, strength, and durability after formal welding.
For pre-welding preheating projects that do not exceed 300°C, the energy consumption of induction heating is more than 3 times that of ceramic sheet (resistance) heating compared with the same power ceramic sheet heating, and the energy saving is as high as 30%-80%.