by Bob Tuzik, January 1, 2005 When NYCTA wanted a new fastener that was 35% “softer” than the softest DF fastener it had in use, a fastener that would not raise the track by more than 1-1/8 inches (30 mm), Dynamic Engineering designed the APT-BF system. The APT-BF fastener incorporates two elastic …
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 …
By Gary P. Wolf • December 1, 2004 “Wide gauge” is one of the most often used FRA derailment codes. In 2003, 254 derailments were reported to have been caused by wide gauge (FRA code T110 or T111). This represents nearly 13% of all derailments reported to the FRA, and roughly …
by Bob Tuzik, December 1, 2004 As part of its effort to monitor dynamic vehicle/track interaction on the Northeast Corridor, Amtrak commissioned ENSCO, Inc., to develop a Wayside Train/Track Interaction Detection System. The goal was to measure and collect information on vehicle/track forces that would enable Amtrak to determine the causes of …
By Bob Tuzik • November 4, 2004 If the first unwritten rule in optimizing the wheel/rail interface on rail transit is: Know your system; the second rule should be: Recognize that the w/r interface is a system. “No single department can attack the issues in isolation and expect to get very far,” Joseph Oriolo, Senior …
By Gary Wolf Part 1 of this article examined trailing-point derailments, facing-point derailments and thin flange wheels. Part 2 examines wheel climb and frog-related derailments. Crosslevel variances in turnout geometry represent a common cause of wheel-climb derailments. It’s not unusual to find bolted or insulated joints within 30 to 40 …
By Gary Wolf No other type of derailment causes as much angst among railroaders as the switch point derailment. The switch point derailment can take several forms, but it generally boils down to a disagreement between the Mechanical Department that blames the switch point, and the Engineering Department that blames …
by Eric E. Magel • September 20, 2004 Wheel wear is an inevitable byproduct of wheel/rail interaction. Excessive wear, however, indicates an imbalance in some aspect of the wheel/rail interface. Amtrak’s high-speed Acela trains, running on track with much greater curvature than other high-speed systems, were quickly found to exhibit very …
By Gary P. Wolf • November 1, 2004 Part 1 of Truck Warp: Causes and Cures covered the three primary causes of truck warp: Part 2 of this article explores these causes in more detail and, more importantly, what can be done to prevent trucks from warping. Lack of sufficient …