Types of rail

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Types of rails 
                           The rails which are used for railway track should be such that every part of the rail can withstand agianst maximum allowable stress . The design cross sectional area of rail should be economically . There are three types of rails are used in the construction of a railway track.
1) Double headed rails
2) Bull headed rails
3) Flat footed rails

1) Double headed rails
                                          Double headed rails having rail section head and foot of same dimensions are termed as double headed rails.
Double headed rails section were used in the early stages of railway. These are designed with a point of view that when top of head which get wear out during the movement of traffic should be replaced with foot , to reuse it when reneeded because head and foot have indentical dimensions thus life of rail can be increased by inverting the rail and reuse it.
2) Bull headed rails
                                     The rails section having there head and foot of difference dimensions are termed as Bull headed rails. In this section head is kept nearly as in double head rails but foot is modified so that minimum required section is kept . These rails are results of the defects arrises in D H. rails . Foot section is kept just to bear the stresses of moving whells loads

Flat footed rails 
                             The rail section having their foot and head is kept nearly as in Bull headed rails. These rails are designed to remove the draw backs. Charles Uigneeles in 1836 invented flat footed rails. These rail can be directly used on sleepers with fine fastening. Later on steel bearing plates are used in between the sleepers and F.F. Rail in order to avoid sinking of rails in to sleepers. These are used in  Indian Railways due to its lateral stability.


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