Auxiliary appliance for examining cross section of steel rail

The utility model discloses an auxiliary appliance for examining the cross section of a steel rail, which simultaneously has the function of examining the positive-negative degree of symmetry of the cross section of the steel rail. The auxiliary appliance comprises a main body, the outline of part edge of the main body basically coincides with the outline of the side edge of the standard cross section of the steel rail, the outlines of the edges are respectively provided with a rail head emboss and a rail bottom abdicating groove, the width of a rail bottom abdicating groove is D1; and when the rail head emboss contacts with the rail head edge of the outline of the side edge, the distance between the rail bottom edge of the outline of the side edge and the rail bottom abdicating groove is D2, and the relation between D1 and D2 is that D2 is larger than 0 and smaller than D1. The auxiliary appliance simultaneously has the function of examining the positive-negative degree of symmetry of the cross section of th