Why Steel Is Used For Rails?
Earlier wooden rails were used on horse drawn wagon ways.The first steel rails used anywhere in the world were laid in Derby station on the Midland Railway in 1857. Steel is a much stronger material, which steadily replaced iron for use on railway rail and allowed much longer lengths of rails to be rolled. Composition of rail steel The basic requirement of rail steel is that it should be hard, wear resistant and crack resistant. This is achieved by steel composition and cooling of the hot rails. These properties of steel are achieved through control of carbon (C) and manganese (Mn) contents. Carbon content of rail steel can go up to a maximum of 0.82 % and manganese content up to a maximum of 1.7 %. The normal rails are made of steel containing 0.7% C and 1% Mn, which are called as C-Mn rail steel. From a strength perspective (ultimate tensile strength of 880 MPa or 90 Kg/ Sq mm), the C-Mn rail is popularly known as 90 UTS rail or Grade 880 rail. This grade of rail