Research on the Development of the Welding Reconditioning Procedure for Friction Liner on the Passenger Coaches

SNTFC CFR SA owns a fleet of 841 passenger coaches, which it maintains through usual overhauls and repairs at high safety levels provided by the national railway regulations and instructions. One of the most important systems of a wagon is the braking system. One part of this system is also the friction liner, its role being to support the friction gasket that applies the braking force on the brake disc. This friction liner is made of cast iron and is a component included in risk class 1A, according to OMT 290/2000, with a service life of 10 years. Depending on the degree of wear and safety in operation, one may decide to replace it with a new part or intervention to return to the initial dimensional shape. Considering the importance of this friction liner, a very precise analysis must be performed, and this should show the steps necessary to reintroduce the part into operation. The performed analysis is a welding reconditioning procedure, which must be applied with precision. The paper indicates all the stages and results we looked for by applying a reconditioning procedure for the particular situation of using the welding process by means of tables / graphs and of results obtained as of detailed works.

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EVALUATION OF THE HOMOGENEITY OF THE WORKING SURFACE OF CAST IRON BRAKE DISCS

Tribologia ◽

10.5604/01.3001.0010.8056 ◽

2017 ◽

Vol 276 (6) ◽

pp. 33-37

Author(s):

Grzegorz KINAL ◽

Marta PACZKOWSKA

Keyword(s):

Cast Iron ◽

Corrosive Wear ◽

Point Of View ◽

Brake Disc ◽

Braking Performance ◽

Brake Pads ◽

Braking System ◽

Brake Discs ◽

The One ◽

Friction Surfaces

This article deals with the one of the most important elements of modern braking systems, which is a brake disc. A brake disc is the one of more stressed parts of the braking system, and its quality and design largely determine the braking performance of the vehicle. The article describes the technology of manufacturing disc brake pads that is important from the point of view of the wear processes occurring between two friction surfaces: the brake disc and the brake pad lining. The research of the cast iron ventilated brake disc surface measured the values of the selected roughness parameters at this site. In the context of measurements, it was also determined to be able to maintain a certain value of selected geometric parameters at a given location for the group of brake discs tested of a specific type and manufactured by a particular manufacturer. The work was carried out in the aspect of the research to create a surface layer to protect the brake discs from the effects of corrosive wear.

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Modeling the Depth of Surface Cracks in Brake Disc

Materials ◽

10.3390/ma14143890 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3890

Author(s):

Wojciech Sawczuk ◽

Mateusz Jüngst ◽

Dariusz Ulbrich ◽

Jakub Kowalczyk

Keyword(s):

Cast Iron ◽

Crack Depth ◽

Brake Disc ◽

Disc Brake ◽

Surface Cracks ◽

Braking System ◽

Brake Discs ◽

Regression Functions ◽

Metallic Object

The article presents the state of knowledge and research in the field of surface cracks occurring in disc braking systems of rail and car vehicles. The craze formed during the operation of vehicles is particularly dangerous and leads to breaking the disc into several pieces. It may lead to a loss of braking force and damage to the entire disc brake caliper. The main aim of the research is to identify surface cracks in brake discs made of cast iron and use experimental methods to estimate their depth. Research were conducted on the disc braking system developed by the authors. In examining the location and depth of cracks, the penetration method, ultrasound, as well as a special probe were used. This device measures the crack depth based on the electrical resistance between two points on the surface of the metallic object. The tests showed that the first microcracks on the brake discs appeared after 309 braking tests on the test stand. In addition, it was observed that the surface cracks length of the disc increased linearly to depth until they reached about 11.5–12 mm with corresponded to crack lengths in the range of 65–70 mm. However, determination of the regression functions presented in the article allows to estimate the depth of surface cracks up to 70 mm long on cast iron brake discs by measuring their length.

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Performance of Hybrid Reinforced Metal Matrix Composite Brake Disc: Simulation Approach

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1025.77 ◽

2021 ◽

Vol 1025 ◽

pp. 77-81

Author(s):

Wei Kang Gan ◽

Nanang Fatchurrohman

Keyword(s):

Cast Iron ◽

Metal Matrix ◽

Structural Performance ◽

Brake Disc ◽

Matrix Composites ◽

Simulation Approach ◽

Ansys Software ◽

Braking System ◽

Brake Discs ◽

Usage Efficiency

A brake disc has an significant role in the vehicle and it is used to stop or decrease the velocity of the vehicle. The demand of metal matrix composites (MMCs) is greatly increased in fabricating the brake disc since it possesses a low density and high thermal conductivity. Over-heating will lead to the malfunction of the braking system and affect the safety of vehicle. Reduced weight of brake disc can decrease the use of fuel of the vehicle thus improve the fuel usage efficiency. This paper is focussed to determine the suitability of AlSiCGr hybrid MMCs compared to cast iron in terms of thermal and structural properties for brake disc. Both design of brake discs was proposed and modelled using CATIA and then imported to ANSYS software for structural and thermal analysis. The simulation results showed that AlSiCGr hybrid MMCs brake disc has higher thermal and structural performance compared to the original cast iron brake disc.

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Numerical Analysis of Novel Design for Ventilated Brake Disc

International Journal of Vehicle Structures and Systems ◽

10.4273/ijvss.8.4.13 ◽

2017 ◽

Vol 8 (4) ◽

Author(s):

A. Krishnan ◽

S.K. Sampat ◽

H. Vinod ◽

M.S. Kumar ◽

P.K.A. Babu

Keyword(s):

Thermal Flux ◽

Heat Energy ◽

Flux Analysis ◽

Brake Disc ◽

Thermal Gradients ◽

Braking System ◽

Disc Brakes ◽

Braking Force ◽

Solid Works ◽

Novel Design

Design of braking system is an important phase in the development of an automobile. During braking, disc brakes accumulate heat energy and high thermal gradients which leads to reduced functionality. This heat has to be dissipated for efficient functioning of brakes. In this paper, a novel design for brake is developed using Solid Works tool. This model aims at maximum dissipation of heat by increasing surface area. A thermal flux analysis of the new model is done to confirm this achievement. A comparative study of other designs of ventilated discs and a plane rotor disc is also done. The calculation and verification of braking force is followed in designing the disc rotor. The main objective is to generate more braking force so as to maximize efficiency. The analyses are done in ANSYS to study and understand the heat flux and temperature that are formed in the disc rotor.

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Study of the Mechanical Behavior of an Automobile Brake Disc

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.15589 ◽

2021 ◽

Author(s):

Kerrouz Siham ◽

Bourdim Mokhtar ◽

Tamine Tawfik ◽

Bouchtara Mostefa

Keyword(s):

Numerical Simulation ◽

Finite Element Method ◽

Finite Element ◽

Service Life ◽

Contact Surface ◽

Brake Disc ◽

The Finite Element Method ◽

Braking System ◽

Fatigue Rupture ◽

The Cost

An automobile brake disc brought into contact with the pads, mechanical stresses are imposed on the contact surface. These stresses can cause degradation by fatigue, rupture, wear, propagation of cracks. Modeling the numerical results makes it possible to recognize this damage in order to improve the braking system, extend its service life, reduce the cost of maintenance and make it more reliable. The aim of our study concerns modeling and numerical simulation using ANSYS 14.5 software based on the finite element method under the influence of certain essential parameters on the braking behavior of the torque as a function of geometric parameters, properties mechanical, boundary conditions, type of loading applied, type of materials chosen and type of analysis carried out in braking torques (ventilated drilled disc / pads and ventilated grooved disc / pads), upon contact with a disc in rotation with a plate which represents the friction body on the disc. The behavior of the torque during braking was analyzed in terms of stresses and deformations, and displacements, the comparison between the two types of discs was also discussed.

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Car braking effectiveness after adaptation for drivers with motor dysfunctions

Open Engineering ◽

10.1515/eng-2021-0060 ◽

2021 ◽

Vol 11 (1) ◽

pp. 617-623

Author(s):

Adam Sowiński ◽

Tomasz Szczepański ◽

Grzegorz Koralewski

Keyword(s):

Efficiency Index ◽

Mathematical Function ◽

Test Results ◽

Braking Performance ◽

Braking System ◽

System Adaptation ◽

Parametric Description ◽

Limited Power ◽

Braking Force ◽

Selection Of

Abstract This article presents the results of measurements of the braking efficiency of vehicles adapted to be operated by drivers with motor dysfunctions. In such cars, the braking system is extended with an adaptive device that allows braking with the upper limb. This device applies pressure to the original brake in the car. The braking force and thus its efficiency depend on the mechanical ratio in the adapting device. In addition, braking performance depends on the sensitivity of the car’s original braking system and the maximum force that a disabled person can exert on the handbrake lever. Such a person may have limited power in the upper limbs. The force exerted by the driver can also be influenced by the position of the driver’s seat in relation to the handbrake lever. This article describes the research aimed at understanding the influence of the above-mentioned factors on the car braking performance. As a part of the analysis of the test results, a mathematical function was proposed that allows a parametric description of the braking efficiency index on the basis of data on the braking system, adaptation device, driver’s motor limitations, and the position of the driver’s seat. The information presented in this article can be used for the preliminary selection of adaptive devices to the needs of a given driver with a disability and to the vehicle construction.

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Intelligent optimization of EV comfort based on a cooperative braking system

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211004461 ◽

2021 ◽

pp. 095440702110044

Author(s):

Lingying Zhao ◽

Min Ye ◽

Xinxin Xu

Keyword(s):

System Model ◽

Regenerative Braking ◽

Coupling Mechanism ◽

Intelligent Algorithm ◽

Distribution Strategy ◽

Braking System ◽

Logic Diagram ◽

Braking Torque ◽

Braking Force ◽

The Time Domain

To address the comfort of an electric vehicle, a coupling mechanism between mechanical friction braking and electric regenerative braking was studied. A cooperative braking system model was established, and comprehensive simulations and system optimizations were carried out. The performance of the cooperative braking system was analyzed. The distribution of the braking force was optimized by an intelligent method, and the distribution of a braking force logic diagram based on comfort was proposed. Using an intelligent algorithm, the braking force was distributed between the two braking systems and between the driving and driven axles. The experiment based on comfort was carried out. The results show that comfort after optimization is improved by 76.29% compared with that before optimization by comparing RMS value in the time domain. The reason is that the braking force distribution strategy based on the optimization takes into account the driver’s braking demand, the maximum braking torque of the motor, and the requirements of vehicle comfort, and makes full use of the braking torque of the motor. The error between simulation results and experimental results is 5.13%, which indicates that the braking force’s distribution strategy is feasible.

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