Reduction of Wheel Squeal in the Path Rapid Transit System

The objective of the work described in this paper is the reduction of annoying wheel squeal produced by a rapid transit car when traversing sharp curves. The paper reviews most of the known methods for reducing wheel squeal, discusses the advantages and disadvantages of the methods, and gives reasons for selection of one method based on the Coulomb friction effect, which consists of a damping ring that is snapped into a groove cut in the steel wheel. Results of tests under operating conditions are given. Conclusion: The use of a damping ring is most effective above 2 KHZ, reaching a significant 9 dB reduction at 5 KHZ in the interior of the transit car.