- Email: [email protected]
Development of onboard friction control
Wear 258 (2005) 1109–1114
Development of onboard friction control Yoshihiro Sudaa,∗ , Takashi Iwasaa , Hisanao Kominea , Masao Tomeokab , Hideki Nakazawab , Kousuke Matsumotob , Takuji Nakaic , Masuhisa Tanimotod , Yasushi Kishimotod a
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba Meguro-ku, Tokyo 153-8505, Japan Rolling Stock Department, Teito Rapid Transit Authority, 3-19-6 Higashi Ueno, Taito-ku, Tokyo 110-0015, Japan Railway Bogie Truck Manufacturing Department, Sumitomo Metal Industries, Ltd., 5-1-109 Shimaya, Konohana-ku, Osaka 554-0024, Japan d Railway System Department, Sumitomo Metal Technology, Inc., 5-1-109 Shimaya, Konohana-ku, Osaka 554-0024, Japan b
c
Received 13 June 2003; received in revised form 28 November 2003; accepted 1 March 2004 Available online 11 November 2004
Abstract 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. © 2004 Elsevier B.V. All rights reserved. Keywords: Friction control; Coefficient of friction; Friction modifier; Wheel/rail wear
1. Introduction Tight curve sections are inevitably constructed in subway lines because of the land limitation. The tight curve sections may cause squeal noise, excessive wear at gauge corner of rail, and wheel, and also rail corrugation. To solve these problems, as a conventional way of controlling the friction coefficient, oil lubricant are supplied between wheel and rail from onboard or wayside device. The oil lubricant proved some effect to solve those problems, however the friction coefficient between wheel and rail keeps very low and may cause wheel skid or slip, therefore application of the oil lubricant should limit neither traction nor braking section of train run∗
Corresponding author. Fax.: +81 354526194. E-mail addresses: [email protected] (Y. Suda), [email protected] (T. Iwasa), [email protected] (H. Komine), [email protected] (M. Tomeoka), h.nakazawa@tokyometro. go.jp (H. Nakazawa), [email protected] (K. Matsumoto), [email protected] (T. Nakai), tanimoto-msh@ sumitomometals.co.jp (M. Tanimoto), kishimot-yss@sumitomometals. co.jp (Y. Kishimoto). 0043-1648/$ – see front matter © 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.wear.2004.03.059
ning. This means that the lubricant cannot be used near the station. On the other hand, there are many tight curve sections adjacent to the station, because the platform section should be designed for straight or curve with large curvature. The authors investigated the application of friction modifier, KELTRACKTM that can maintain appropriate friction coefficient between wheel and rail [1]. By two-roller rig test, traction coefficient of the friction modifier has been obtained. As shown in Fig. 1, the coefficient of traction by the friction modifier has positive creep characteristics. While the slip rates increase up to 2%, the coefficient of traction of the friction modifier increases. Furthermore, some test results with experimental bogie truck at the train depots have been obtained by spraying the friction modifier on rail [2]. For Japanese subway, which has both frequent train service and many tight curves in their service lines, the authors propose that the friction modifier should be applied from the commercial train to top of the rail. The advantages of onboard friction control system are as follows: the friction modifier can be supplied onto rail uniformly by control of its amount in proportion to the vehicle’s speed, and the train with friction
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Fig. 3. Creep characteristics of friction modifier. Fig. 1. Creep characteristics of friction modifier.
control device can supply the friction modifier to any curve sections where wheel/rail contact condition should be controlled, and the specific equipped trains can control friction coefficient between wheel and rail all over the service line.
2. Onboard friction control system 2.1. System concept Fig. 2 shows the concept of onboard friction control. From the tail end of a train set the friction modifier is sprayed on top of the inner rail at the specific curve section. The following trains running through the sprayed section, wheels of these trains contact with the modifier, and then the friction coefficient between wheel and rail can be controlled. Fig. 3 shows another results of two-roller rig test. The friction modifier is supplied repeatedly at regular intervals and the slip rate between two rollers is 2% constantly. As a result, the coefficient of traction gets lower than the dry condition as shown in Fig. 1 after the 30 s test finished. This result suggests that the intermittent supply of friction modifier can make an appropriate condition of coefficient of traction. 2.2. Onboard friction control system Onboard friction control devices are equipped to both ends of a train set as shown in Fig. 4. This system consists of some
devices equipped on the vehicle and identification tag (ID tag) installed on track. When the train comes to curve section, transponder under the vehicle can detect the beginning of the curve by receiving signal from the ID tag at the start point of curve section, then a certain amount of friction modifier in proportion to the vehicle’s speed is sprayed vertically on top of the inner rail from the nozzle equipped to trailing bogie truck of the last car, therefore this train does not tread on the modifier on rail. Amount of the modifier can be determined by the frequency of trains, which pass through the curve section and also by the curvature of the test section. Sprayed modifier on rail quickly dry out since it is water based solution and after it dry out only the particle of the friction modifier still remain on the top of the rail. The following train after the spraying train passes through the curve and its wheels contact with the modifier on rail, as the results the following train(s) can take merits of friction control. Vehicle has been equipped the devices consisting of control unit, modifier supplying, spraying nozzle and transponder as shown in Fig. 5. Friction modifier control unit (FMC) can control the valve to supply pressurized air to the nozzle and also can control the rotation of motor and pump to supply variable amount of modifier determined by vehicle’s speed. Motor, pump, air valves and modifier tank are the components of friction modifier supplying unit (FMS). In a case of rain while the equipped trains running in an open section, the signal of wiper-unit working can stop to spray. Fig. 6 shows the friction modifier sprayed on the rail at train depot.
Fig. 2. Concept of onboard friction control.
Y. Suda et al. / Wear 258 (2005) 1109–1114
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Fig. 4. Test train with onboard friction control system.
Fig. 7. Curve section for field test.
running through this section are all 20 m-length bogie truck vehicles. Trains run through this curve section at balanced speed for cant. Fig. 7 shows dimensions of the test track. Corrugations are generated on top of the inner rail under the conventional oil lubricant condition, and its wavelength reaches approximate 60 mm. Total number of the trains running through this section varies from 70 to 120 a day. Fig. 5. Components of onboard friction control system.
Fig. 6. Friction modifier sprayed on rail.
3. Field running test 3.1. Test condition To evaluate the friction control system, onboard devices have been installed to the vehicle of a subway line, Teito Rapid Transit Authority, Tokyo, Japan. The service line has a tight curve suitable for evaluation of the friction control system; radius is only 147 m for narrow gauge line, and trains
3.2. Field running test result As the first step of evaluation, the test train has been equipped the onboard friction control device, and then field running test with measuring wheelset has been carried out. This wheelset can measure vertical and lateral force acting on the wheel individually. Firstly, the test train has run the curve section under the dry condition without friction control, and then the train ran through the curve section after the friction modifier had been sprayed. Fig. 8 and Table 1 shows the result that the lateral force of the inner wheel has decreased all through the curve section because of uniform modifier spraying on the inner rail. Thin lines in Fig. 8 show the result without friction control, and bold lines show the result of friction control. Table 1 shows peak values of the measured data. As a result of the friction control of the inner wheel, lateral force of the outer wheel also decreased, and the ratio of lateral force to vertical force (L/V) of the outer wheel that indicates Table 1 Field running test result Outer wheel
Dry conditon Friction controlled Decrease (%)
Inner wheel
Lateral force (kN)
L/V
Lateral force (kN)
L/V
36.5 21.0 42
0.78 0.44 44
30.5 12.5 59
0.83 0.22 73
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Fig. 9. Commercial train for field test.
Fig. 8. Field running test result.
the curving performance of vehicle decreased by 44% from the dry condition with the decrease of L/V of inner wheel by 59% as shown in Table 1. The result also shows the reduction of lateral force fluctuation of the inner rail that may cause corrugations [3]. These results prove the effectiveness of the onboard friction control system.
4. Long-term observation 4.1. Test condition As the second step of evaluation, long-term observation of the service running trains has been carried out. In order to evaluate various effects of friction modifier other than the curving performance, lateral and vertical force on rail, sound level beside the rail and also lateral acceleration of the rail have been measured at circular curve section of the test curve. Fig. 9 shows the commercial train running through the test curve section. The test train equipped the onboard friction control device ran almost everyday under commercial operation. The measuring data have been collected when every train with or without the onboard friction control device passed through the curve section.
Fig. 10. L/V of inner rail under dry and wet condition.
Fig. 11 shows the results under the condition of friction controlled, where the trains passing with spraying the modifier are indicated by inverted triangles. Number of trains with spraying friction modifier is different at stage, since the numbers of trains pass through the test curve section are varied day by day. As early phase of the test, L/V of the inner rail decreased just after the test train passed with spraying the modifier, however the L/V value increased to ordinary dry level after some trains without friction control passed. The test has been carried out continuously for 6 months with the test train under the service running condition. As the last phase of the test after 6 months later, L/V of the inner rail settled at lower level all a day than the conventional condition without friction control as shown in Fig. 10.
4.2. L/V of inner rail In order to evaluate the effectiveness of friction control, the data under the dry condition without friction control have been measured. Fig. 10 shows the results of L/V at the inner rail indicating the friction coefficient between wheel and rail, which keep high levels from 0.4 to 0.5, against that under the wet condition without friction control, L/V of the inner rail varied the levels from 0.2 to 0.5.
Fig. 11. L/V of inner rail under friction controlled condition.
Y. Suda et al. / Wear 258 (2005) 1109–1114
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Fig. 12. L/V of outer rail under dry and wet condition. Fig. 15. Lateral acceleration of rail under friction controlled condition.
Fig. 13. L/V of outer rail under friction controlled condition.
4.3. L/V of outer rail Fig. 16. Sound level beside rail under dry and wet condition.
In comparison with the conventional dry or wet condition, L/V value of the outer rail has also been decreased. Fig. 12 shows results under the conventional conditions. Under the dry condition, L/V of the outer rail keeps its level at 0.5 all day, while under the friction controlled condition, as shown in Fig. 13, it reduced to about 0.3. After 6 months later, it settled about 0.3 even between the two trains with the onboard friction control devices passed. 4.4. Lateral acceleration on inner rail The lateral acceleration of the inner rail, which causes corrugation of the inner rail, has been measured. Acceleration pickup is attached to web of the rail where lateral and vertical forces are measured. The acceleration pickup can move laterally and measured data are filtered with low pass filter at 100 Hz. Under the dry condition, the peak level of lateral acceleration sometimes reached over 100 m/s2 as shown in Fig. 14. Against that, by applying the friction modifier, the acceleration reduced its level lower than 20 m/s2 as shown in Fig. 15. The corrugation at the inner rail has disappeared completely after 6 months test, since the acceleration settled in lower level all day.
Fig. 17. Sound level beside rail under friction controlled condition.
4.5. Sound level When the train runs through the tight curve section, squeal noise between wheel and rail sometimes reaches over 100 dB beside the rail. To confirm the effect of onboard friction control, microphone is installed beside the rail. The height of the microphone is approximate 40 cm from the top of the rail, and the lateral distance from the wheel/rail contact is approximate 1 m. Under the dry and wet condition, sound level beside the rail has been measured as shown in Fig. 16. After the friction modifier was applied to rail, sound level of the trains reduced with the decrease of squeal noise between wheel and rail. The results are shown in Fig. 17.
5. Summary
Fig. 14. Lateral acceleration of rail under dry and wet condition.
The authors have developed the onboard friction control system for commercial trains. Field test shows decrease of L/V value of the wheelset and also the decrease of lateral force fluctuation. Long-term observation by commercial train shows the various effects of the friction control such as L/V
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Y. Suda et al. / Wear 258 (2005) 1109–1114
value, lateral acceleration of rail and also sound level beside rail.
References [1] J. Kalousek, K.L. Johnson, An investigation of short pitch wheel and rail corrugations on the Vancouver mass transit system, Proc. Instn. Mech. Eng. (1992) 127–135.
[2] M. Tomeoka, N. Kabe, M. Tanimoto, E. Miyauchi, M. Nakata, Friction control between wheel and rail by means of on-board lubrication, Wear 253 (2002) 124–129. [3] A. Matumoto, Y. Sato, H. Ono, M. Tanimoto, Y. Oka, E. Miyauchi, Formation mechanism and countermeasures of corrugation on curved track, Wear 253 (2002) 178–184.
Development of onboard friction control Yoshihiro Sudaa,∗ , Takashi Iwasaa , Hisanao Kominea , Masao Tomeokab , Hideki Nakazawab , Kousuke Matsumotob , Takuji Nakaic , Masuhisa Tanimotod , Yasushi Kishimotod a
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba Meguro-ku, Tokyo 153-8505, Japan Rolling Stock Department, Teito Rapid Transit Authority, 3-19-6 Higashi Ueno, Taito-ku, Tokyo 110-0015, Japan Railway Bogie Truck Manufacturing Department, Sumitomo Metal Industries, Ltd., 5-1-109 Shimaya, Konohana-ku, Osaka 554-0024, Japan d Railway System Department, Sumitomo Metal Technology, Inc., 5-1-109 Shimaya, Konohana-ku, Osaka 554-0024, Japan b
c
Received 13 June 2003; received in revised form 28 November 2003; accepted 1 March 2004 Available online 11 November 2004
Abstract 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. © 2004 Elsevier B.V. All rights reserved. Keywords: Friction control; Coefficient of friction; Friction modifier; Wheel/rail wear
1. Introduction Tight curve sections are inevitably constructed in subway lines because of the land limitation. The tight curve sections may cause squeal noise, excessive wear at gauge corner of rail, and wheel, and also rail corrugation. To solve these problems, as a conventional way of controlling the friction coefficient, oil lubricant are supplied between wheel and rail from onboard or wayside device. The oil lubricant proved some effect to solve those problems, however the friction coefficient between wheel and rail keeps very low and may cause wheel skid or slip, therefore application of the oil lubricant should limit neither traction nor braking section of train run∗
Corresponding author. Fax.: +81 354526194. E-mail addresses: [email protected] (Y. Suda), [email protected] (T. Iwasa), [email protected] (H. Komine), [email protected] (M. Tomeoka), h.nakazawa@tokyometro. go.jp (H. Nakazawa), [email protected] (K. Matsumoto), [email protected] (T. Nakai), tanimoto-msh@ sumitomometals.co.jp (M. Tanimoto), kishimot-yss@sumitomometals. co.jp (Y. Kishimoto). 0043-1648/$ – see front matter © 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.wear.2004.03.059
ning. This means that the lubricant cannot be used near the station. On the other hand, there are many tight curve sections adjacent to the station, because the platform section should be designed for straight or curve with large curvature. The authors investigated the application of friction modifier, KELTRACKTM that can maintain appropriate friction coefficient between wheel and rail [1]. By two-roller rig test, traction coefficient of the friction modifier has been obtained. As shown in Fig. 1, the coefficient of traction by the friction modifier has positive creep characteristics. While the slip rates increase up to 2%, the coefficient of traction of the friction modifier increases. Furthermore, some test results with experimental bogie truck at the train depots have been obtained by spraying the friction modifier on rail [2]. For Japanese subway, which has both frequent train service and many tight curves in their service lines, the authors propose that the friction modifier should be applied from the commercial train to top of the rail. The advantages of onboard friction control system are as follows: the friction modifier can be supplied onto rail uniformly by control of its amount in proportion to the vehicle’s speed, and the train with friction
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Fig. 3. Creep characteristics of friction modifier. Fig. 1. Creep characteristics of friction modifier.
control device can supply the friction modifier to any curve sections where wheel/rail contact condition should be controlled, and the specific equipped trains can control friction coefficient between wheel and rail all over the service line.
2. Onboard friction control system 2.1. System concept Fig. 2 shows the concept of onboard friction control. From the tail end of a train set the friction modifier is sprayed on top of the inner rail at the specific curve section. The following trains running through the sprayed section, wheels of these trains contact with the modifier, and then the friction coefficient between wheel and rail can be controlled. Fig. 3 shows another results of two-roller rig test. The friction modifier is supplied repeatedly at regular intervals and the slip rate between two rollers is 2% constantly. As a result, the coefficient of traction gets lower than the dry condition as shown in Fig. 1 after the 30 s test finished. This result suggests that the intermittent supply of friction modifier can make an appropriate condition of coefficient of traction. 2.2. Onboard friction control system Onboard friction control devices are equipped to both ends of a train set as shown in Fig. 4. This system consists of some
devices equipped on the vehicle and identification tag (ID tag) installed on track. When the train comes to curve section, transponder under the vehicle can detect the beginning of the curve by receiving signal from the ID tag at the start point of curve section, then a certain amount of friction modifier in proportion to the vehicle’s speed is sprayed vertically on top of the inner rail from the nozzle equipped to trailing bogie truck of the last car, therefore this train does not tread on the modifier on rail. Amount of the modifier can be determined by the frequency of trains, which pass through the curve section and also by the curvature of the test section. Sprayed modifier on rail quickly dry out since it is water based solution and after it dry out only the particle of the friction modifier still remain on the top of the rail. The following train after the spraying train passes through the curve and its wheels contact with the modifier on rail, as the results the following train(s) can take merits of friction control. Vehicle has been equipped the devices consisting of control unit, modifier supplying, spraying nozzle and transponder as shown in Fig. 5. Friction modifier control unit (FMC) can control the valve to supply pressurized air to the nozzle and also can control the rotation of motor and pump to supply variable amount of modifier determined by vehicle’s speed. Motor, pump, air valves and modifier tank are the components of friction modifier supplying unit (FMS). In a case of rain while the equipped trains running in an open section, the signal of wiper-unit working can stop to spray. Fig. 6 shows the friction modifier sprayed on the rail at train depot.
Fig. 2. Concept of onboard friction control.
Y. Suda et al. / Wear 258 (2005) 1109–1114
1111
Fig. 4. Test train with onboard friction control system.
Fig. 7. Curve section for field test.
running through this section are all 20 m-length bogie truck vehicles. Trains run through this curve section at balanced speed for cant. Fig. 7 shows dimensions of the test track. Corrugations are generated on top of the inner rail under the conventional oil lubricant condition, and its wavelength reaches approximate 60 mm. Total number of the trains running through this section varies from 70 to 120 a day. Fig. 5. Components of onboard friction control system.
Fig. 6. Friction modifier sprayed on rail.
3. Field running test 3.1. Test condition To evaluate the friction control system, onboard devices have been installed to the vehicle of a subway line, Teito Rapid Transit Authority, Tokyo, Japan. The service line has a tight curve suitable for evaluation of the friction control system; radius is only 147 m for narrow gauge line, and trains
3.2. Field running test result As the first step of evaluation, the test train has been equipped the onboard friction control device, and then field running test with measuring wheelset has been carried out. This wheelset can measure vertical and lateral force acting on the wheel individually. Firstly, the test train has run the curve section under the dry condition without friction control, and then the train ran through the curve section after the friction modifier had been sprayed. Fig. 8 and Table 1 shows the result that the lateral force of the inner wheel has decreased all through the curve section because of uniform modifier spraying on the inner rail. Thin lines in Fig. 8 show the result without friction control, and bold lines show the result of friction control. Table 1 shows peak values of the measured data. As a result of the friction control of the inner wheel, lateral force of the outer wheel also decreased, and the ratio of lateral force to vertical force (L/V) of the outer wheel that indicates Table 1 Field running test result Outer wheel
Dry conditon Friction controlled Decrease (%)
Inner wheel
Lateral force (kN)
L/V
Lateral force (kN)
L/V
36.5 21.0 42
0.78 0.44 44
30.5 12.5 59
0.83 0.22 73
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Fig. 9. Commercial train for field test.
Fig. 8. Field running test result.
the curving performance of vehicle decreased by 44% from the dry condition with the decrease of L/V of inner wheel by 59% as shown in Table 1. The result also shows the reduction of lateral force fluctuation of the inner rail that may cause corrugations [3]. These results prove the effectiveness of the onboard friction control system.
4. Long-term observation 4.1. Test condition As the second step of evaluation, long-term observation of the service running trains has been carried out. In order to evaluate various effects of friction modifier other than the curving performance, lateral and vertical force on rail, sound level beside the rail and also lateral acceleration of the rail have been measured at circular curve section of the test curve. Fig. 9 shows the commercial train running through the test curve section. The test train equipped the onboard friction control device ran almost everyday under commercial operation. The measuring data have been collected when every train with or without the onboard friction control device passed through the curve section.
Fig. 10. L/V of inner rail under dry and wet condition.
Fig. 11 shows the results under the condition of friction controlled, where the trains passing with spraying the modifier are indicated by inverted triangles. Number of trains with spraying friction modifier is different at stage, since the numbers of trains pass through the test curve section are varied day by day. As early phase of the test, L/V of the inner rail decreased just after the test train passed with spraying the modifier, however the L/V value increased to ordinary dry level after some trains without friction control passed. The test has been carried out continuously for 6 months with the test train under the service running condition. As the last phase of the test after 6 months later, L/V of the inner rail settled at lower level all a day than the conventional condition without friction control as shown in Fig. 10.
4.2. L/V of inner rail In order to evaluate the effectiveness of friction control, the data under the dry condition without friction control have been measured. Fig. 10 shows the results of L/V at the inner rail indicating the friction coefficient between wheel and rail, which keep high levels from 0.4 to 0.5, against that under the wet condition without friction control, L/V of the inner rail varied the levels from 0.2 to 0.5.
Fig. 11. L/V of inner rail under friction controlled condition.
Y. Suda et al. / Wear 258 (2005) 1109–1114
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Fig. 12. L/V of outer rail under dry and wet condition. Fig. 15. Lateral acceleration of rail under friction controlled condition.
Fig. 13. L/V of outer rail under friction controlled condition.
4.3. L/V of outer rail Fig. 16. Sound level beside rail under dry and wet condition.
In comparison with the conventional dry or wet condition, L/V value of the outer rail has also been decreased. Fig. 12 shows results under the conventional conditions. Under the dry condition, L/V of the outer rail keeps its level at 0.5 all day, while under the friction controlled condition, as shown in Fig. 13, it reduced to about 0.3. After 6 months later, it settled about 0.3 even between the two trains with the onboard friction control devices passed. 4.4. Lateral acceleration on inner rail The lateral acceleration of the inner rail, which causes corrugation of the inner rail, has been measured. Acceleration pickup is attached to web of the rail where lateral and vertical forces are measured. The acceleration pickup can move laterally and measured data are filtered with low pass filter at 100 Hz. Under the dry condition, the peak level of lateral acceleration sometimes reached over 100 m/s2 as shown in Fig. 14. Against that, by applying the friction modifier, the acceleration reduced its level lower than 20 m/s2 as shown in Fig. 15. The corrugation at the inner rail has disappeared completely after 6 months test, since the acceleration settled in lower level all day.
Fig. 17. Sound level beside rail under friction controlled condition.
4.5. Sound level When the train runs through the tight curve section, squeal noise between wheel and rail sometimes reaches over 100 dB beside the rail. To confirm the effect of onboard friction control, microphone is installed beside the rail. The height of the microphone is approximate 40 cm from the top of the rail, and the lateral distance from the wheel/rail contact is approximate 1 m. Under the dry and wet condition, sound level beside the rail has been measured as shown in Fig. 16. After the friction modifier was applied to rail, sound level of the trains reduced with the decrease of squeal noise between wheel and rail. The results are shown in Fig. 17.
5. Summary
Fig. 14. Lateral acceleration of rail under dry and wet condition.
The authors have developed the onboard friction control system for commercial trains. Field test shows decrease of L/V value of the wheelset and also the decrease of lateral force fluctuation. Long-term observation by commercial train shows the various effects of the friction control such as L/V
1114
Y. Suda et al. / Wear 258 (2005) 1109–1114
value, lateral acceleration of rail and also sound level beside rail.
References [1] J. Kalousek, K.L. Johnson, An investigation of short pitch wheel and rail corrugations on the Vancouver mass transit system, Proc. Instn. Mech. Eng. (1992) 127–135.
[2] M. Tomeoka, N. Kabe, M. Tanimoto, E. Miyauchi, M. Nakata, Friction control between wheel and rail by means of on-board lubrication, Wear 253 (2002) 124–129. [3] A. Matumoto, Y. Sato, H. Ono, M. Tanimoto, Y. Oka, E. Miyauchi, Formation mechanism and countermeasures of corrugation on curved track, Wear 253 (2002) 178–184.