By Gary Wolf • January, 2006 Railroad engineering managers have been struggling with the problem of how much elevation to place in a curve since the first steam engines started turning a wheel. While the physics and calculus of the matter seem straightforward, the application of those formulas is where problems …
by Peter Klauser • October 2005 Cant deficiency has a significant effect on curving performance of vehicles in both passenger and freight service. The forces due to centrifugal acceleration through a curve must ultimately be reacted at the wheel/rail interface. Curve lateral acceleration and the compensating effect of track superelevation can …
by Bill O’Donnell • July 4, 2005 As part of its efforts to reduce the stress state on North American railroads, the Association of American Railroads (AAR) mandated that all new cars ordered after January 1, 2002, must be equipped with constant contact side bearings. Constant contact side bearings (CCSBs) raise the threshold …
By Bob Tuzik • May 26, 2005 The Federal Railroad Administration’s Office of Research and Development is not the best known R&D organization in the industry, but it is one of the most important. It’s work figures prominently in rulemaking and the regulatory process for the industry. That role is …
By Gary Wolf • May 04, 2005 Part 1 of this two-part article explored the importance of roller style side bearings in maintaining proper vehicle performance and how improper maintenance of side bearings can directly affect wheel/rail forces. Part 2 examines the purpose, types of designs and maintenance of the …
by Bob Tuzik, January 1, 2005 Any problem affecting the New York City Transit is by default a big problem. The process of transporting more than four million passengers per day in 6,000 vehicles on more than 700 miles of elevated, underground at-grade mainline tracks, on a system that operates 24 hours …
By Gary Wolf • April 04, 2005 Side Bearings serve as support elements on the truck bolster and are located to the side of the centerplate. The function of the side bearing is to support the underside of the car body bolster in the event the car leans to one side …
By Gary Wolf • February 1, 2005 It’s said that “it takes two to tango,” but it takes three critical elements to induce harmonic rock and roll: • An operating speed between approximately 12 and 24 mph. • A vehicle conducive to rocking due to its mass and spring characteristics. • …
by Bob Tuzik, December 1, 2004 Investigations have shown that wheel-flange/gauge-face angle and the coefficient of friction (COF) play significant roles in contributing to or preventing flange-climb derailments. Investigations have also shown that Light Rail Vehicles with Independently Rotating Wheels (IRWs) have a greater propensity for flange-climb derailment than vehicles with conventional …
By Gary P. Wolf • January 1, 2005 Part 1 of “Effects of Wide Gauge on Derailment Potential” examined how wide gauge occurs, some of the symptoms and reasons why wide gauge is undesirable. Part 2 of this article explores how to correctly measure gauge and properly identify wide gauge …