Sleepers protect points from failure

Problem: . Where there are points, and if the movement exceeds tolerances, the resulting vibration is transferred to the point mechanism, eventually causing it to fail. Solution: Hertfordshire-based Product Innovation and Gentech International from Ayrshire were approached by the University of Birmingham School of Engineering to jointly develop a method of continuously measuring rail movement at points. The development work being part of the University's collaboration with Railtrack and Carillion Rail in the development a fault detection monitoring system for the UK network. Product Innovation developed both ultrasonic and electromechanical devices with the electromechanical version being deemed to be the most effective. The final solution comprises a large post driven into the ground beside the relevant sleeper. Attached to this is the unit, including a large spring which exerts a continuous force on the sleeper. Attached to the base of the spring in contact with the sleeper is a flexible vertical rod. The upper end of which is located in a tube. At the top of the rod is a magnet which interacts with a series of magnetically operated electric switches on the inside of the tube. As the rod moves up and down, it operates different switches, thus indicating its position. A rubber boot covers the spring area of the unit. Applications: The first two prototype Point Void Meters have been installed at a major junction on the Birmingham to Bristol line, and have been in place since January. Two more prototypes have been installed at Leominster in Herefordshire. The technology is appropriate to the monitoring of any structure where excessive movement may indicate a growing problem. TS Product Innovation