By Bob Tuzik • January, 2007 Friction control plays a major role in reducing wear, noise and vibration, and managing wheel/rail interaction on rail transit systems. Controlling friction has become more achievable with the advent of engineered friction modifiers and improvements to wayside and onboard application systems for both traditional lubricants …
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 Bob Tuzik February 1, 2005 There are two primary approaches to friction management on rail transit systems: onboard and wayside. The most effective method depends upon the demands of the system. A relatively small system with consistent degrees of curvature, for example, might lend itself to onboard application. A system with …
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 Huimin Wu and Semih Kalay • October, 2009 Wear and rolling contact fatigue (RCF) of rails and wheels are common problems under heavy-haul operations. Increasing axle loads can increase the capacity of a railway system, but also can increase the stress state of the system. A root cause of RCF …
By Huimin Wu and Semih Kalay • January 2010 See Part 1 of this article here. What are the differences between rail shapes that produce higher contact conicities and those that produce lower contact conicities? The profiles shown in Figures 1a and 1b illustrate the differences that can result in significant …
By Norman Hooper • July 2010 See Part 1. Experience has shown that an efficient and cost-effective rail grinding program requires attention to basic track inspection and maintenance procedures. This includes attention to “hot spots,” such as joints, welds and road crossings. Figure 1 shows a rail joint at the end …
By Mike Roney • July, 2009 Canadian Pacific has taken a unique approach to reducing the stress state in its western corridor. The approach includes the implementation of distributed power and the implementation of friction management. It also includes examination of their combined effects — something that is relatively new. Looking at …
By Norman Hooper • January 2010 It behooves railways to periodically review tie, fastener and surfacing maintenance practices, particularly as they relate to the planning and quality of rail grinding procedures. The use of technology, enhanced inspections, regular grinding cycles and friction modification can improve rail surface quality. The safety rationale …
By Rob Caldwell • October 2010 The wheel/rail interface is a complex system – one that benefits greatly from careful pre-engineering. There are significant benefits from properly addressing the wheel/rail interface, and serious consequences from allowing the interface to govern itself. While there are examples of both pre- and post-engineering scenarios, there …