Contact Model And Simulation Analysis of Rail Grinding With Open-Structured Abrasive Belt Based On Pressing Plate

Abstract Recently, the emerging rail grinding method with open-structured abrasive belt based on pressing plate which adopts full contour copying grinding method to extend the working length of abrasive belt and is more suitable for preventative grinding and maintenance of rail corrugation in high-speed railway has been proposed. The essence of its grinding process is the complex nonlinear interaction among the pressing plate, abrasive belt and rail. The research on the contact mechanism of the rail grinding method with open-structured abrasive belt based on pressing plate is still very lacking, which limits the practical application of the emering rail grinding method to a certain extent. In this paper, a theoretical model of the contact between pressing plate, abrasive belt and rail is established. The contact area morphology and contact stress distribution were obtained, and validity of the theoretical model was verified by finite element simulation. At the same time, the distribution characteristics of contact stress under single concentrated force, uniform force and multiple concentrated force were studied based on the contact model. It is concluded that the multiple concentrated force is the optimal loading method, and the contact stress is more uniform, which is more conducive to repair the standard contour of rail.

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Rail Corrugation of High-Speed Railway Induced by Rail Grinding

Shock and Vibration ◽

10.1155/2021/5546809 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Xing Du ◽

Xuesong Jin ◽

Guotang Zhao ◽

Zefeng Wen ◽

Wei Li

Keyword(s):

High Speed ◽

Field Tests ◽

Vertical Vibration ◽

Clear Correlation ◽

High Speed Rail ◽

Rail Corrugation ◽

Rail Grinding ◽

Initial Excitation ◽

Technical Operation ◽

Grinding Stone

Rail corrugation is a common railway defect that involves diverse and complex factors. Rail grinding is also the most commonly used method to address corrugations. Through numerous irregularity tests and one-third octave frequency spectrum analyses, this study determined the characteristics and development process for rail corrugation on high-speed rail tracks. The vibration transmission properties of the grinding train were tested using the force hammer impacting method. Thereafter, using a simulation, the influence of the vertical vibration behavior of the grinding stone and the stiffness of the hydraulics were determined. Through a series of field tests and numerical simulations, this study revealed a clear correlation between rail corrugation and rail grinding and confirmed that the technical operation of rail grinding is closely associated with regular grinding marks at a wavelength of approximately 60 mm on rail surfaces. The combination of the natural vibration of the grinding stone (frequency of 60 Hz) and an inappropriate operational process can aggravate the grinding marks on the rail surfaces, thereby forming an initial excitation of rail corrugation. Although a large number of irregularity tests are performed after rail grinding, these wavelength-fixing grinding marks can cause the formation and development of rail corrugation. Suggestions for improving the high-speed rail-grinding technology are also provided.

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Microscopic contact pressure and material removal modeling in rail grinding using abrasive belt

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420932419 ◽

2020 ◽

Vol 235 (1-2) ◽

pp. 3-12

Author(s):

Wengang Fan ◽

Wenxi Wang ◽

Junda Wang ◽

Xinle Zhang ◽

Chang Qian ◽

...

Keyword(s):

Surface Topography ◽

Contact Pressure ◽

Material Removal ◽

Normal Load ◽

Great Influence ◽

Theoretical Models ◽

Contact Behavior ◽

Abrasive Belt ◽

Grinding Method ◽

Rail Grinding

Recently, the emerging rail grinding method using abrasive belt has been proposed to efficiently achieve the required geometric profile and the surface quality of the railhead. Although the abrasive features indeed have a great influence on this rail grinding process, the surface topography of abrasive belt regarding grits at the microscopic scale is neglected. In this article, a microscopic contact pressure model was developed to reveal the contact behavior of every active grit based on the digital representation of the surface topography of abrasive belt. Then a numerical model of material removal quantity was also established based on the consideration of the characteristics of abrasive grits and their interactions. Finally, the series of finite element simulations and grinding tests were successively implemented. The normal load and the surface topography of abrasive belt significantly affected the microscopic contact behavior of grits, thus confirming the proposed theoretical models of microscopic contact pressure and material removal quantity.

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Efficient rail grinding method considering progress process of rail corrugation

The Proceedings of the Transportation and Logistics Conference ◽

10.1299/jsmetld.2018.27.3204 ◽

2018 ◽

Vol 2018.27 (0) ◽

pp. 3204

Author(s):

Hirofumi TANAKA ◽

Kazuhiro KAJIHARA ◽

Masashi MIWA

Keyword(s):

Rail Corrugation ◽

Grinding Method ◽

Rail Grinding

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A Theoretical Model of Rail Corrugation on a Slab Track

ICTE 2015 ◽

10.1061/9780784479384.150 ◽

2015 ◽

Author(s):

Xia Li ◽

Xueshan Zhang ◽

Jian Zhang ◽

Jun Zhang ◽

Zefeng Wen ◽

...

Keyword(s):

Theoretical Model ◽

Rail Corrugation ◽

Slab Track

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Thermo-stress coupling field of friction lining during high-speed slide of wire rope in a mine friction-drive hoist

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406211430596 ◽

2011 ◽

Vol 226 (9) ◽

pp. 2154-2167 ◽

Cited By ~ 6

Author(s):

Yu-xing Peng ◽

Zhen-cai Zhu ◽

Min-ming Tong ◽

Guo-an Chen ◽

Yan-hai Cheng ◽

...

Keyword(s):

Theoretical Model ◽

Contact Zone ◽

Constitutive Relation ◽

High Speed ◽

Thermomechanical Properties ◽

Element Analysis ◽

Coupling Field ◽

Zone Ii ◽

Coefficient Of Linear Expansion ◽

Friction Lining

In order to seek the intrinsic reason for the serious high-speed slide accident in a mine hoist, the thermo-stress coupling field of friction lining was studied during the high-speed slide. First, the helical contact characteristics were analysed. Subsequently, the thermomechanical properties and the dynamic coefficient of linear expansion were studied, and the thermomechanical constitutive relation was obtained. Then, the theoretical model of thermo-stress was established with the consideration of the helical contact characteristics and the thermomechanical constitutive relation. Also, the numerical simulation was performed by the finite element analysis. Finally, the experiment was carried out on a friction tester. It is found that the temperature is the highest at the contact zone II and the friction heat focuses on the contact surface layer. The variation frequency of the stress is 6.98 Hz at 0.5 m/s. Besides, the catastrophe for the strain and coefficient of friction occurs at 3 m/s. The thermo-stress concentration occurs at contact zone II. The experiment results agree with the simulation ones, which validates the theoretical model of thermo-stress.

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Intermittent Gliding in the Hunting Flight of the Kestrel, Falco Tinnunculus L

Journal of Experimental Biology ◽

10.1242/jeb.102.1.1 ◽

1983 ◽

Vol 102 (1) ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

J. J. VIDELER ◽

D. WEIHS ◽

S. DAAN

Keyword(s):

Theoretical Model ◽

Wind Speed ◽

High Speed ◽

Flapping Flight ◽

Falco Tinnunculus ◽

Fixed Position ◽

Centre Of Gravity ◽

High Speed Film

The hunting flight of the kestrel (Falco tinnunculus) consists of short bouts of flight at wind speed against the wind with the eyes in a fixed position relative to the ground, and of short flights from one such position to the next. High speed films taken with a camera in a fixed position of a hunting kestrel of known weight and dimensions, allow estimates to be made of the amount of energy required for this behaviour. A theoretical model shows how a bird could economise by alternating flapping flight with short gliding bouts, without changing the position of the eyes above the ground, by mere displacement of the centre of gravity relative to the head. High speed film data confirm predictions from this model.

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Modeling of contact stress and tool-based frictional forces considering edge effect through material separation exploration

10.21203/rs.3.rs-313988/v1 ◽

2021 ◽

Author(s):

Weiwei Zhang ◽

Jian Weng ◽

Kejia Zhuang ◽

Cheng Hu ◽

Xing Dai ◽

...

Keyword(s):

Finite Element ◽

Shear Stress ◽

Contact Stress ◽

Finite Element Simulations ◽

Cutting Edge ◽

Contact Model ◽

Feature Points ◽

Normal Contact ◽

Frictional Forces ◽

Material Separation

Abstract Cutting tools with round edge can enhance the performance of machining difficult-to-machine materials, while the complex contact mechanism related to micro cutting edge limits the deeper understanding of cutting mechanics. Material separation, which is associate to plough mechanism with formation of dead metal zone (DMZ), also requires the analysis of contact behavior. This study develops a contact model along the round edge together with the illustration of DMZ, with three contact feature points defined to explain the contact situation between workpiece and cutting edge. Among these feature points, two separation points related to DMZ classify the sliding and sticking region considering the dual-zone approach. The stagnation point is the zero shear stress point where a sudden change in shear stress direction happens. Besides, the parabolic stress model obtained from finite element simulations is established to define the normal contact distribution along the round edge. In this basis, the tool-based frictional forces are determined and two contact force components are classified for different contact regions. The proposed contact feature points and contact stress are validated through illustration with finite element simulations. Besides, orthogonal cutting tests ensure the practicality and accuracy of the proposed contact model and predicted cutting forces.

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