Interface - The Journal of Wheel/Rail Interaction

EDITORIAL

Delving into Wheel/Rail Data
July, 2008

This issue of Interface incorporates an array of information about the work being done by railroads, researchers and suppliers from around the world to integrate technology that improves vehicle/track interaction.

The lead article, Part 1 of “Wheel/Rail Interaction ’08: Data to Information,” incorporates information presented at Advanced Rail Management and Progressive Railroading magazine's 14th annual seminar devoted to wheel/rail interaction. The article provides information on Norfolk Southern’s pilot program to implement electronically controlled pneumatic (ECP) braking on a portion of its coal fleet. Results, thus far, indicate that trains equipped with ECP brakes are able to stop in less than half the distance of those equipped with conventional braking systems. As of May 2008, NS is operating six ECP train sets in two operating regions.

Rail wear under heavy axle loads (HAL) is also covered. AAR- and FRA-funded revenue service tests to quantify the effects of HAL operation on track components have shown that premium rails have performed well, with an estimated wear life of up to 1,000 MGT on 10-degree curves with “excellent” gauge-face and top-of-rail friction control.

Wheel maintenance is another primary area of concern relating to vehicle/track interaction — particularly in light of the industry’s annual $350-million cost of wheel tread damage. The Wheel Defect Prevention Research Consortium (WDPRC), which was formed to identify the causes of and cures for wheel damage, determined that the primary defect mechanisms were shelling on coal cars, a mix of spalling and shelling on non-coal cars, and thermal mechanical shelling on intermodal cars. Surprising, perhaps, is that the movement of cars with handbrakes applied was shown to be the primary cause of wheel spalling.

Rail Profile Grinding
Anders Frick of Banverket, the Swedish Rail Administration, and Dr. Wolfgang Schoech of Speno International SA examine the ongoing effort to design and implement appropriate rail profiles on European railways. They look at rail grinding’s evolution from a corrective intervention to the preventive approach (in which thin layers of metal are removed at regular intervals) that is becoming the standard, today.

Still, fundamental questions about the best profile or profiles to be applied remain. As the authors point out in “Target Profiles for Rail Grinding: A Never Ending Story,” one rail profile cannot accommodate all conditions. “Experience has shown that even new rail profiles, as-rolled and installed in track, do not provide ideal contact conditions for the wheels. Consequently, grinding worn rails to their original profile does not always improve wheel/rail contact conditions. Instead, a number of rail profiles have been developed to improve wheel/rail interaction and extend the life of rail.”

The authors present findings from years of experience on European railways, and the move toward standardization of rail profile designs for various track and operating conditions.

Implementing Technology
This issue also examines the ways in which wayside measurement technologies are implemented on North American railways. “Implementing Wheel/Rail Measurement and Analysis Technology” presents the salient points made by key industry practitioners during a panel discussion at Advanced Rail Management and Progressive Railroading magazine's Wheel/Rail Interaction ’08 Seminar.

“There is a great deal of interest from around the world in what we're doing in the way of wayside measurement and fault-detection, and how the information it generates can improve safety and the reliability of the rail network,” the session moderator, Amtrak’s Mike Franke pointed out in his introductory remarks.

And while the road from the design of new technologies to full implementation can be long and expensive, the overall benefits have been worth the effort. The ability to identify potentially damaging high-impact wheel loads and derailment-prone bad acting vehicles has driven the industry’s use of wayside detection systems to unprecedented levels. BNSF’s wayside detector network, alone, has grown from its initial network of six stand-alone detectors, using two different technologies, to 72 stand-alone detectors, using 12 different technologies. (BNSF also employs a network of 763 warm-bearing detectors.)

If anything, the railway industry does not give itself enough credit for embracing technology in the manner that it has. “I have seen more change in this industry in the past eight years than I saw in 20 years in the automotive industry,” said Lisa Stabler, BNSF’s Assistant Vice President for Quality and Reliability Engineering, and a self-characterized “outsider.” When it’s important, she said, “It's amazing how quickly this industry can move.” And when you come down to it, she said, “It's an exciting time — a golden age for detector technology.”

Noise and Vibration
Also in this issue, GERB Schwingungsisolierungen GmbH & Co.KG’s Hans-Georg Wagner provides a clinic on the use of “High-Performance Mass-Spring-Systems to Reduce Noise and Vibration in Track.”

Noise and vibration associated with railway operations has become a significant issue in metropolitan areas around the world. Among vibration-mitigating measures, mass-spring systems represent an efficient method of reducing vibration directly at the source. Mr. Wagner points out that mass-spring systems, which use soft steel coil springs in resiliently supported concrete track slabs, provide the lowest achievable system frequencies to attenuate vibration-related dB levels. These types of systems are used in tunnels, at grade and on elevated tracks on all types freight and passenger lines.

Enjoy the issue

Bob Tuzik
Publisher