2. Manufacturing and usage. The rail is rolled by carbon killed steel smelted in an open hearth furnace and an oxygen converter. Its purpose is to withstand the operating pressure and impact load of rolling stock.
The steel rail after rolling should be straight without any significant bending or twisting. The local bending and torsion of light and heavy rails, as well as the amount of correction deformation, and the inclination of rail end faces, shall not exceed the standard. The surface of steel rail should be clean and smooth, free of defects such as cracks, scars, scratches, etc.; there should be no shrinkage marks and interlayers on the end surface. The allowable defects on the overall surface of the light and heavy rail and the extent of their geometric quantities shall not exceed the standard.