Sparks Fly at Rail Welding!

KC Streetcar Constructors began welding the rail into track for the KC Streetcar Main Street Extension on Wednesday, January 26.

If you pass by 27th & Main Street, you might see some sparks. KC Streetcar Constructors are welding more than 700 tons of steel that will make up half the track needed for the KC Streetcar Main Street Extension.

Using a technique called electric flash-butt welding, the ends of two 80-foot sticks of rail are heated to approximately 2,800 degrees and then pressed together to create the weld. Each weld takes less than 10 minutes to complete. Five sticks will be welded together into one 400’ string. By completing the electric flash-butt weld now, the team minimizes the number of welds needed in the field during track construction, which maximizes schedule efficiency.

Welding will take approximately two weeks to complete, weather permitting.

Rail Welding Steps

1. The ends and web (the area between the head and base) of the rail are polished for a clean electrical path for the weld process.

2. Two rail sticks are rolled to the welding machine. The welder aligns the two rail sticks and clamps the welding machine onto the two pieces of rail.

3. Sparks fly as a large amount of electrical current is induced into the metal, creating a short circuit between the rail sticks that heats the rail up. During this process, the weld head pushes the two rail sticks together and a forge weld is created.

4. When the weld is complete, an internal shear removed the weld from the forge process. After the welder comes off the rail is pulled to another area where workers will grind the weld down and measure it with a straight edge to ensure the weld meets the required specifications.

5. After the grind is complete, the rail is pulled to another area for an inspector to perform tests verifying a solid, successful weld. Once all welds on the string are approved it will be moved to the rail storage area.