The function of sanding gears in rail vehicles consists in general of the conveyance of sand which is transmitted from a holding tank to a tapered crack between wheel and rail. The transmitted sand causes an increase of the sticking friction. Through the function of the sanding gears the rail vehicle achieves, on the one hand a shorter braking distance and on the other hand an improvement of the slip behaviour of the wheel on the rail; for example during the start-up process of the railway.
The ZIV-sanding gears are adjusted by the principle of the injector. The compressed-air required for the loss of the sand is either produced by a maintenance-free compressor which is included in delivery, or is provided by a central compressed-air system of the rail vehicle.
Electronically control systems for the quantities of sand, heatable sand injectors, charging level censors, as well as the appropriate flaps for filling in sand and dump mounting parts belong to the optional equipment of the ZIV-sanding gears.