Measurement of wheel–rail contact forces is very important, but it is not executed so often because of its difficulties. A new measuring method introduced in this paper can measure such contact ...forces without special wheelsets equipped with strain gauges and slip rings or telemeters. In this method the lateral contact force is measured from the lateral distortion of wheel measured directly by several non-contact gap sensors. Normal and longitudinal contact forces are also measured from the deflection of spring or the strain of parts of the bogies except wheelsets. According to the results of full-size bogie stand tests and train running tests, it is verified that the new method has sufficient practicability of monitoring the contact forces on commercial lines.
By using non-contact gap sensors equipped on non-rotating parts of a bogie, a new measuring method of wheel/rail contact forces has been developed. The developed system has been verified to have ...sufficient durability for continuous measurement on in-service trains and sufficient practical accuracy after various stand tests and train running tests. After a long-period of continuous measurement on a commercial subway line, some important characteristics of wheel/rail contact mechanics were found by the analysis of measured data. Numerical simulations of curving with a full vehicle model using multi-body dynamics software were carried out, and according to the comparison with measured data, simulation results agree well with measured data in the steady-state values of derailment coefficients considering friction coefficient.
The purpose of this study is to demonstrate the friction control between wheel and rail can solve wheel/rail contact problems, such as wheel-slipping, rail corrugation, squeak noises, wheel/rail wear ...and so on. Firstly, fundamental tests with two-roller-rigs were carried out to evaluate the friction performances of several types of friction modifiers. Then, for the purpose of realizing the friction control with them, authors developed an on-board system, which sprayed friction modifier from a bogie to the top of rail accurately. This method is very advantageous to control friction between wheel and rail. As a result of track tests, it was found that one type of friction modifier, which had proper coefficient of friction (COF) and positive creep characteristics, was very effective to reduce the lateral force and the squeak noises.
A new measuring method introduced in this paper can measure contact forces between wheel and rail without special wheel-set with slip rings or telemeters. In this method the lateral contact force is ...measured from the lateral distortion of wheel measured directly by several non-contact gap sensors. Normal and longitudinal contact forces are also measured from the deflection of spring or the strain of parts of the bogies except special wheel-set. This new method, unlike the conventional method, is able to store the data everyday on every curve of commercial lines, which change according to friction coefficient and train running speed and so on. In this paper the authors describe the new measuring method without strain-gauge-equipped wheel-set, estimations of comparing the new method and the conventional method, and data analysis of measurements by commercial service trains. Practicable use of this new method enables us to easily obtain the statistical data of derailment coefficients with an on-board measuring method. Statistically analyzing the variation of rail-lubrication conditions and characteristics of wheel-rail contact force on every curve with this new system can help to improve track conditions for maintenance.
Controlling the friction between wheel and rail is direct and very effective measures to improve the curiving performances of railway trucks, because the curving performances depend much on friction ...characteristics Authors have proposed a method, “fnction control”, which utilizes friction modifier (KELTRACK™ HPF) with onboard spraying system With the method, not only friction coefficient, but also fuction characteristics can be controlled as expected In this study, MBD simulation is very valuable tool to foresee the effect of the control in advance of experiment with real car And the creep characteristics of wheel/rail contact with the fuction modifier takes very important role in the simulation In this paper, authors propose a theoretical model of wheel/rail contact condition considering the creep characterstics of friction modifier, which is derived the application of principle tribological theories
Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of railway trucks, because the curving performances depend much on friction ...characteristics. Authors have proposed a method, 'friction control', which utilizes friction modifier ($KELTRACK^{TM}$ HPF) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics can be controlled as expected. In this study, MBD simulation is very valuable tool to foresee the effect of the control in advance of experiment with real car. And the creep characteristics of wheel/rail contact with the friction modifier takes very important role in the simulation. In this paper, authors propose a theoretical model of wheel/rail contact condition considering the creep characteristics of friction modifier, which is derived the application of principle tribological theories.
Development of onboard friction control Suda, Yoshihiro; Iwasa, Takashi; Komine, Hisanao ...
Wear,
03/2005, Letnik:
258, Številka:
7
Journal Article, Conference Proceeding
Recenzirano
Onboard friction control system has been developed for vehicles of Tokyo Subway (TRTA). In subway lines, there are many tight curves that may cause squeal noise, excessive wear of rail and also rail ...corrugation. To solve these various problems, onboard friction control system has been developed and has been equipped to commercial trains. The effect of friction control has been confirmed by the field running test with measuring wheelset. After that, under the service running condition of the equipped trains, the long-term observation proved the effect of the friction control by reducing L/V value (the ratio of lateral (L) and vertical (V) force between wheel and rail), lateral acceleration of inner rail and also sound level beside rail.
A Method to Apply Friction Modifier in Railway System MATSUMOTO, Kosuke; SUDA, Yoshihiro; IWASA, Takashi ...
JSME International Journal Series C Mechanical Systems, Machine Elements and Manufacturing,
06/2004, Letnik:
47, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of bogie trucks, because the curving performances of bogie truck depend much ...on friction characteristics. Authors have proposed a method, “friction control”, which utilizes friction modifier (KELTRACKTM HPF) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics are able to be controlled as expected. In this paper, results of fundamental experiments are reported which play an important role to realize the new method.
Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of railway trucks, because the curving performances of truck depend much on ...friction characteristics. Authors have proposed a method, “friction control”, which utilizes friction modifier (KELTRACKTM HPF) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics are able to he controlled as expected. In this paper, results of fundamental experiments are reported which play an important role to realize the new method.
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