FIST Railway Spring Clip (Elastic Rail Clip) The rail is the component that supports and guides the rolling stock. It is secured to the sleepers in the track bed by means of elastic fastenings. The spring clip (elastic clip) is the principal clamping element of an elastic fastening: through bending and torsional deformation of the clip, it generates the clamping force (toe load) that acts on the rail, thereby ensuring a reliable long-term connection between rails, preserving the structural integrity of the track, restraining longitudinal and lateral movement of the rail relative to the sleeper, and maintaining the correct track gauge — thus guaranteeing the safe running of rail vehicles. In addition, since wheel-to-rail contact is rigid (steel-on-steel), vibration is unavoidable. The clip's special elastic structure also enables it to absorb the impact energy generated by passing vehicles, providing a damping effect. The spring clip works under repeated alternating (cyclic) stress, subject to bending, torsion, fatigue and corrosion, as well as extremely high instantaneous impact loads as vehicles pass. Performance requirements are therefore extremely stringent. - @jacqueslees