Influence of Track Properties on Railway Vehicles Wheel Rolling Contact Fatigue

2008 ◽  
Author(s):  
Mahdi Mehrgou ◽  
Asghar Nasr
Keyword(s):  
Rolling Contact Fatigue ◽  
Tangential Force ◽  
Contact Fatigue ◽  
Contact Forces ◽  
Rolling Contact ◽  
Vehicle Dynamic ◽  
Wheel Load ◽  
Wheel Rolling ◽  
Railway Passenger ◽  
Vehicle Dynamic Simulation

Track properties such as rail inclination, cant and gage width have significant effects on the shape and size of the contact area, actual rolling radius and also on the contact forces. These effects have an important role on rolling contact fatigue (RCF) which is known to be the main reason for large portion of wheel set failures and expenses. In this study the wheel/rail dynamic interaction of an Iranian railway passenger wagon under different track features are investigated through simulations using ADAMS\Rail commercial software. The calculated results regarding contact load data and contact properties of the wheel and rail are used for fatigue analysis to calculate RCF damage to the wheels using damage criteria based on previous studies. Two major parameters believed to have serious roles on RCF are the contact stress and the tangential force in the contact patch. These parameters are obtained from vehicle dynamic simulation studies. This paper describes and compares effects of different track geometries in curved and tangent tracks on RCF of three different wheel profiles S1002, P8 and IR1002. It is to identify which combinations of wheel load, wheel and rail profiles and vehicle dynamic characteristics cause RCF more severely.

Rail RCF and the Effects of Different Wheel Profiles

2008 ◽  
Author(s):  
Mehdi Mehrgou ◽  
Asghar Nasr
Keyword(s):  
Dynamic Simulation ◽  
Rolling Contact Fatigue ◽  
Tangential Force ◽  
Contact Fatigue ◽  
Simulation Software ◽  
Contact Forces ◽  
Rolling Contact ◽  
Dynamic Interactions ◽  
Railway Passenger ◽  
Vehicle Dynamic Simulation

Wheel lateral profile has considerable effects on the wheel/rail dynamic interactions such as the shape and size of the contact area, instantaneous rolling radius and contact forces. Theses themselves have indirectly important roles on the rolling contact fatigue (RCF) which is known to be the main reason for large portion of rail maintenance costs. In this study the wheel/rail dynamic interaction of an Iranian railway passenger wagon under three different wheel profiles are investigated using ADAMS\Rail commercial simulation software. The dynamic simulation results regarding contact load and contact features of the wheel and rail are used for fatigue analysis to calculate RCF damage to the rail using reliable damage criteria reported in the literature. The two major parameters having serious roles on the RCF are believed to be the contact stress and the tangential force at the contact patch. These parameters are obtained from vehicle dynamic simulation studies. This paper describes and compares the effects of three different wheel profiles known as S1002, P8 and IR1002 on the rail RCF in both the curved and tangent sections of a track. The primary results clearly identify the effects of wheel profile on the RCF.

scholarly journals Investigation on Wheel-Rail Contact and Damage Behavior in a Flange Bearing Frog with Explicit Finite Element Method

2019 ◽  
Vol 2019 ◽  
pp. 1-17
Author(s):  
Yuan Gao ◽  
Ping Wang ◽  
Yibin Liu ◽  
Jingmang Xu ◽  
Zhiguo Dong ◽  
...  
Keyword(s):  
Finite Element ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Numerical Procedure ◽  
Contact Forces ◽  
Rolling Contact ◽  
Fe Model ◽  
Wheel Load ◽  
Explicit Finite Element ◽  
Contact Behavior

Flange bearing frogs are designed to provide continuous rolling surfaces for trains traveling on the through line, but the interaction between wheel and rail in a diverging line is more complex than that for a common crossing, especially including flange bearing mode and multipoint contact during the transition. The wheel load will be transited from tread to flange and back to tread, which will intensify the wheel-rail interaction. In this paper, a numerical procedure is presented for the analysis of wheel-rail rolling contact behavior and damage prediction for the flange bearing frog. The three-dimensional explicit finite element (FE) model of a wheel passing the flange bearing frog is established to obtain the dynamic wheel-rail interaction in both the facing and the trailing move. The evolution of contact forces, the distribution of adhesion-slip regions, and shear surface stress and microslip at the contact patch are revealed. Then, the competition relationship between RCF (rolling contact fatigue) and wear of a flange bearing frog is analyzed. The results of numerical simulations can contribute to an understanding of the mechanism of the transient rolling contact behavior and provide guidance in design optimization for flange bearing frogs.

Numerical analysis of the influence of liquid on propagation of a rolling contact fatigue crack

2017 ◽  
Author(s):  
Mirosaw Olzak ◽  
Janusz Piechna ◽  
Pawe Pyrzanowski
Keyword(s):  
Fatigue Crack ◽  
Reynolds Equation ◽  
Rolling Contact Fatigue ◽  
Fluid Motion ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wheel Load ◽  
One Dimensional ◽  
Wheel Rolling ◽  
Crack Faces

Numerical investigations of the propagation of rolling contact fatigue crack filled by the liquid have been conducted. Two models of fluid – crack interaction have been considered. In the first model called “hydrostatic” the assumption of incompressible, inviscid and weightless liquid was accepted. It was also assumed that due to the wheel load the trapped liquid could not get outside the crack and its volume remained constant until the rising pressure would open up the crack mouth again. On this assumption the analysis has a steady-state character. In the second model it has been assumed that the crack is filled by the viscous, incompressible fluid and the fluid motion as well as the resulting pressure distribution can be represented by one-dimensional form of the Reynolds equation. The method for solving the problem of the coupled motion of liquid and crack faces has been developed and series of calculation were made. The method has been employed for the predicting of crack deformation in the course of wheel rolling.

The Effects of Wheelset Position and Operating Environment on Rolling Contact Fatigue

2008 ◽  
Author(s):  
Scott M. Cummings ◽  
Paul Krupowicz
Keyword(s):  
Environmental Factors ◽  
Impact Load ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Contact Forces ◽  
Rolling Contact ◽  
Minor Role ◽  
Operating Environment ◽  
Lead Position ◽  
Defect Prevention

The Wheel Defect Prevention Research Consortium (WDPRC) conducted analyses of wheel impact load detector (WILD) data to explore how wheelset position and operating environment affect rolling contact fatigue (RCF). The typical three-piece freight car truck used in North America produces higher tangential wheel/rail contact forces on the wheelset in the lead position than on the wheelset in the trail position of a truck as a car negotiates a curve. An analysis of WILD data shows that these higher forces are contributing to more shelling damage on wheelsets that are consistently in the lead position of a truck. Datasets in which the cars are frequently oriented with the A-end leading show the largest percentage of elevated WILD readings in the lead position of the lead truck (axle 4) followed by the lead position of the trail truck (axle 2). Likewise, datasets in which the cars are frequently oriented with the B-end leading show the largest percentage of elevated WILD readings in the lead position of the lead truck (axle 1) followed by the lead position of the trail truck (axle 3). Additionally, datasets in which there is an equal mix of car orientations show a much more evenly distributed location of elevated WILD readings. Another analysis of WILD data from five trainsets of nearly identical cars shows that any differences in wheel tread damage due to component differences are insignificant in comparison to the differences in wheel tread damage associated with environmental factors. While this analysis does not address component specification differences that could potentially have a large influence on shelling (such as M-976 trucks in comparison to standard trucks), it does show that environmental factors can play a large role in wheel tread damage. Car routing and loading characteristics were investigated as possible wheel damage factors. It appears that cars running on routes through terrain with longer, steeper grades may be prone to increased wheel shelling, probably due to thermal mechanical shelling (TMS). Side-to-side imbalanced loading appears to play a minor role in wheel shelling for two of the five trainsets.

Investigating the Rolling Contact Fatigue in Rails Using Finite Element Method and Cohesive Zone Approach

2018 ◽  
Author(s):  
Mohamad Ghodrati ◽  
Mehdi Ahmadian ◽  
Reza Mirzaeifar
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Grain Boundaries ◽  
Fatigue Damage ◽  
Cohesive Zone ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wheel Load ◽  
Element Method

A micromechanical-based 2D framework is presented to study the rolling contact fatigue (RCF) in rail steels using finite element method. In this framework, the contact patch of rail and wheel is studied by explicitly modeling the grains and grain boundaries, to investigate the potential origin of RCF at the microstructural level. The framework incorporates Voronoi tessellation algorithm to create the microstructure geometry of rail material, and uses cohesive zone approach to simulate the behavior of grain boundaries. To study the fatigue damage caused by cyclic moving of wheels on rail, Abaqus subroutines are employed to degrade the material by increasing the number of cycles, and Jiang-Sehitoglu fatigue damage law is employed as evolution law. By applying Hertzian moving cyclic load, instead of wheel load, the effect of traction ratio and temperature change on RCF initiation and growth are studied. By considering different traction ratios (0.0 to 0.5), it is shown that increasing traction ratio significantly increases the fatigue damage. Also by increasing traction ratio, crack initiation migrates from the rail subsurface to surface. The results also show that there are no significant changes in the growth of RCF at higher temperatures, but at lower temperatures there is a measurable increase in RCF growth. This finding correlates with anecdotal information available in the rail industry about the seasonality of RCF, in which some railroads report noticing more RCF damage during the colder months.

Thermal Effects on Wheel Performance Based on Twin Disc Testing

2020 ◽  
Author(s):  
Dingqing Li ◽  
Monique Stewart
Keyword(s):  
Thermal Effects ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Contact Forces ◽  
Rolling Contact ◽  
Test Machine ◽  
Testing Program ◽  
Different Types ◽  
Different Temperatures ◽  
Surface Performance

Abstract This paper presents the results and findings from a testing program conducted to investigate how temperature at the wheel-rail interface may affect wheel surface performance; i.e., development of rolling contact fatigue (RCF) and wear. Under this testing program, a twin disc test machine was used to test two different types of wheel specimens (cast and forged) under a range of temperatures (ambient to 800° F) and slip ratios from 0 to 0.75 percent. This testing program included a total of 32 tests, covering two wheel materials, four different temperatures, four slip ratios, and various traction coefficients as a ratio of longitudinal and vertical wheel/rail contact forces.

On the wheel rolling contact fatigue of high power AC locomotives running in complicated environments

Wear ◽  
2019 ◽  
Vol 436-437 ◽  
pp. 202956 ◽  
Author(s):  
Yongfeng Liu ◽  
Tao Jiang ◽  
Xin Zhao ◽  
Zefeng Wen ◽  
Shulin Liang
Keyword(s):  
High Power ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wheel Rolling

Approaches to modeling occurrence of rolling contact fatigue damages in rails

2018 ◽  
Vol 77 (5) ◽  
pp. 259-268 ◽  
Author(s):  
S. M. Zakharov ◽  
E. V. Torskaya
Keyword(s):  
Laboratory Tests ◽  
Rolling Contact Fatigue ◽  
Tangential Force ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Joint Zone ◽  
The Road ◽  
Heavy Haul ◽  
Vehicle Movement ◽  
Relative Slippage

Rolling contact-fatigue damages of rails along with their wear are the most common types of rail defects. In recent years, there have been significant changes in the distribution of rolling contact fatigue damages of rails especially on railways operating under heavy haul conditions.This paper is devoted to the overview of approaches to modeling of the occurrence of rolling contact fatigue (RCF) damages on working surfaces of rails. Four types of such approaches to modeling are considered. The first is based on the methods of contact mechanics. To realize it, the vehicle movement on the characteristic sections of the track is modeled, the forces acting in contact are determined, the contact problem is solved, and the values of the linear criterion of contact fatigue damage are determined. The required characteristics of rolling contact fatigue of the rail material are established on the basis of laboratory tests. The second approach uses the diagram of the adaptability of rail material to cyclic loads, proposed by K. Johnson, established on the basis of laboratory tests. The third approach uses criteria that have the physical meaning of the energy released at the contact as an index of the product of the tangential force in contact and relative slippage. In the fourth approach predicting the accumulation of plastic deformation under conditions of cyclic loading is performed on the basis of a series of standard tests of rail steels, including in the welded joint zone, and finite element modeling. In addition, there is also a probabilistic model, based on the assumption that it is possible to transfer the results of the RCF damage of rails on the experimental section of the road to any other site.As the conclusion the authors formulated directions for further studies on the formation and development of surface rolling contact fatigue defects in rails.

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