|Rick Gagne posted|
Jon K. Kristinsson Does not include the current standard 136.
Saturday, March 10, 2018
Rail Weight History
Just one image, but a lot of history. The weight labels are the weight of one yard of rail. Note the size of the rail went down in 1965 when steel became economic to make and replaced iron. That is because steel is stronger than iron. To develop the T-rail shape, they had to develop rolling mills that could apply enough pressure between the rolls to force the metal into the wider shapes.