The development of a low creep regime, hand-operated tribometer

Following research in 2000 in which the benefits of using lateral creep to establish friction levels in the wheel/rail contact region were established, the author and his team pushed the operating regime to include the smaller, slower realm of hand-operated tribometry. Implementing and managing of both flange lubrication, and top of rail friction modification programs have become more widely adopted and hence there is a growing need for measurements that assist in quantifying the effectiveness of these programs. Likewise, the need to measure the success of these programs has become paramount. The current design, hand-push tribometer widely used throughout the world has limitations previously outlined and operators have pressed for improvements both in operating convenience and, in particular, in controlling the operating regime that defines the values produced. The key element is in maintaining a low creep or percent slip condition that any particular measurement is associated with. The original tribometer and its predecessors were not capable of controlling creep in the few percent range. A related limitation in previous designs was the tendency to have the measuring wheel momentarily stop, thereby leaving one spot on the wheel susceptible to rapid changes to its local condition. In the new design, for each increment of forward motion, the measurement wheel always rolls to a new position of both the measurement wheel and the rail. (C) 2008 Harold Harrison. Published by Elsevier B.V. All rights reserved.