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Article
Publication date: 2 September 2014

Qingrui Meng

The aim of this work is to reveal the temperature rise characteristics of the new designed disc during a braking process. In underground coal mines, the highest temperature of the…

Abstract

Purpose

The aim of this work is to reveal the temperature rise characteristics of the new designed disc during a braking process. In underground coal mines, the highest temperature of the disc brake used for inclined downward belt conveyors should be < 150 to prevent gas explosion during a braking process. To meet the requirements, a new type of disc was designed.

Design/methodology/approach

By using ANSYS software, the disc surface and interior temperature rise variations, effect of braking time and running speed on temperature rise are analyzed numerically.

Findings

The results show that the new designed disc can meet the coal mines’ requirements well, during the braking process the disc surface temperature increases at first and then decreases, there is an obvious temperature gradient in the axial direction; when running speed increases to two times of the rated one, the highest temperature nearly reaches 150; and a prolonged braking time can decrease the highest temperature effectively.

Research limitations/implications

It indicates that the disc brake should act as earlier as possible to slow down the belt conveyor when overspeed occurs; and when the running speed increases to two times of the rated one, the braking time must be prolonged to prevent gas explosion.

Originality/value

Research findings of this paper provides theoretical basis for the practical applications of the disc brake used for inclined downward belt conveyor.

Details

Industrial Lubrication and Tribology, vol. 66 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 6 October 2023

Youjie Chen, Rong Fu, Junying Yang, En Zhang, Linlin Su and Fei Gao

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Abstract

Purpose

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Design/methodology/approach

Three friction blocks with different COFs are examined by a TM-I-type reduced-scale inertial braking dynamometer. On this basis, the thermo-mechanically coupled model of friction pairs is established to study the evolution of brake disc temperature under different COFs using ADINA software.

Findings

Results indicate that the calculated disc temperature field matches the experimental well. The effect of COF on the peak temperature is magnified by the braking speed. With the COF increasing, the rise rate of instantaneous peak temperature is accelerated, and the dynamic equilibrium period and cooling-down period are observed in advance. The increase in COF promotes the area ratio of the high-temperature zone and the maximum radial temperature difference. When the COF is increased from 0.245 to 0.359 and 0.434 at 140 km/h, the area ratio of high-temperature zone increases from 12% to 44% and 49% and the maximum radial temperature difference increases from 56°C to 75°C and 83°C. The sensitiveness of the axial temperature difference to the COF is related to the braking time. The maximum axial temperature difference increases with COF in the early stages of braking, while it is hardly sensitive to the COF in the later stages of braking.

Originality/value

The effect of COF on the aluminum-based brake disc temperature is revealed, providing a theoretical reference for the popularization of aluminum-based brake discs and the selection of matching brake pads.

Details

Industrial Lubrication and Tribology, vol. 75 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 19 April 2023

Meixian Zhang, Hanbo Shi, Siyuan Ding and Lei Ma

The purpose of this paper is to study the influence of braking speed at –20 °C on the wear property of high-speed railway braking materials and the temperature also stress…

Abstract

Purpose

The purpose of this paper is to study the influence of braking speed at –20 °C on the wear property of high-speed railway braking materials and the temperature also stress analyses of brake disc friction surface.

Design/methodology/approach

Friction brake tester was used to simulate the wear test of high-speed railway braking materials at diverse braking speeds (2,100, 2,400, 2,700 and 3,000 rad/min) at –20 °C and the stress and temperature analyses of brake disc friction surface were carried out by COMSOL.

Findings

Compared with 20°C, there is initial stress of brake disc friction surface before brake starting; also, the maximum wear depth is larger at –20°C. Besides, at –20 °C, with the rising of braking speed, the graphite particles on the friction surface of brake pad significantly reduce. And scratches and cracks are formed on brake pad friction surface. Besides, the abrasive wear, adhesive wear and thermal cracks of brake disc friction surface are aggravated. Moreover, the maximal worn depth also increase. Meanwhile, the highest temperature and the maximum thermal stress of brake disc friction surface both raise. Furthermore, the temperature and thermal stress gradients at radial direction of brake disc friction surface aggrandize, which makes the thermal cracks on brake disc friction surface further exacerbated.

Research limitations/implications

In this paper, the wear property of the high-speed railway braking materials is studied by combining experiment and simulation. However, due to the low-speed traveling of high-speed railway was mainly studied in this paper, there may be no comprehensive simulation of the real running condition of high-speed railway. At the same time, the working condition of low-temperature environment cannot be completely simulated and controlled.

Practical implications

The research results of this paper provide a basic instruction for other researchers and also provide an important reference for relevant personnel to choose the braking speed of high-speed railway at –20 °C.

Social implications

The research of this paper provides a brick for the study of high-speed railway braking materials and also provides some references for the safe service of trains in low-temperature environment.

Originality/value

This paper studied the wear property and carried out the simulation analysis of braking materials at –20 °C at diverse braking speed. The research findings provide an important reference for the selection of braking speed of high-speed railway at –20 °C.

Details

Industrial Lubrication and Tribology, vol. 75 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 22 August 2022

Youjie Chen, Fei Gao, Rong Fu, Linlin Su, Xiaoming Han and Junying Yang

This study aims to clarify the relationship of friction material type and brake disc temperature through braking experiment.

Abstract

Purpose

This study aims to clarify the relationship of friction material type and brake disc temperature through braking experiment.

Design/methodology/approach

The braking performances of resin materials (RM), semimetallic materials (SM) and copper-based powder metallurgy materials (PM) friction blocks mating with forged steel brake disc were examined based on TM-I-type reduced-scale inertial braking dynamometer. The brake disc surface temperature was recorded by infrared thermal camera during braking.

Findings

Experimental results indicate that the thermal wear resistance of three friction materials differs with mental content, resulting in the deviation of pad-disc system contact state during braking, thus forming different temperature distribution on the brake disc surface. The peak temperature on the disc face of RM (190°C) is 36.6% and 45.4% lower than that of PM (300°C) and SM (348°C) at 160 km/h. The maximum radial temperature deviation of PM (35°C) is approximately three times than that of RM (12°C) and 40% higher than that of SM (25°C) at 50 km/h, whereas the maximum temperature deviation of SM (97°C) is six times than that of RM (16°C) and 31% higher than that of PM (74°C) at 160 km/h.

Originality/value

The effect of friction material type on the disc surface temperature distribution is revealed, which provides a meaningful reference for the design of brake friction pairs and choice of brake pad materials.

Details

Industrial Lubrication and Tribology, vol. 74 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 March 2022

Lei Ma, Hanbo Shi, Siyuan Ding, Chao Zhang, Haibing Yuan and Junlin Pan

The purpose of this paper is to study the wear of railway brake disc/pad in low-temperature environment and to explore the damage form of brake disc/pad materials and the law of…

Abstract

Purpose

The purpose of this paper is to study the wear of railway brake disc/pad in low-temperature environment and to explore the damage form of brake disc/pad materials and the law of temperature rise in braking process and its influence on friction pair material damage.

Design/methodology/approach

The influence of ambient temperature on tribological properties of brake materials was studied by using low-temperature environment simulation device and MM-1000 high-speed brake testing machine. The law of temperature rise in the braking process was simulated by temperature field module of COMSOL.

Findings

The damage of disc sample increases with the decrease of ambient temperature, and the main damage form is furrow. With the decrease of ambient temperature, pitting corrosion, wear, spalling and cracks appear successively. The maximum temperature of brake disc decreases linearly with the decrease of ambient temperature. However, when the ambient temperature is 0 in the experiment, the surface temperature of the disc will increase abnormally because of the increase of abrasive particles caused by the toughening and brittleness transformation of the material.

Originality/value

In this paper, through the study of train braking in low-temperature environment, the damage mechanism and law of train braking pair in low-temperature environment are found, which provide some basis for the development of high-speed railway in low-temperature environment.

Details

Industrial Lubrication and Tribology, vol. 74 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 17 August 2020

Ali Belhocine and Oday Ibraheem Abdullah

This study aims to investigate numerically a thermomechanical behavior of disc brake using ANSYS 11.0 which applies the finite element method (FEM) to solve the transient thermal…

Abstract

Purpose

This study aims to investigate numerically a thermomechanical behavior of disc brake using ANSYS 11.0 which applies the finite element method (FEM) to solve the transient thermal analysis and the static structural sequentially with the coupled method. Computational fluid dynamics analysis will help the authors in the calculation of the values of the heat transfer (h) that will be exploited in the transient evolution of the brake disc temperatures. Finally, the model resolution allows the authors to visualize other important results of this research such as the deformations and the Von Mises stress on the disc, as well as the contact pressure of the brake pads.

Design/methodology/approach

A transient finite element analysis (FEA) model was developed to calculate the temperature distribution of the brake rotor with respect to time. A steady-state CFD model was created to obtain convective heat transfer coefficients (HTC) that were used in the FE model. Because HTCs are dependent on temperature, it was necessary to couple the CFD and FEA solutions. A comparison was made between the temperature of full and ventilated brake disc showing the importance of cooling mode in the design of automobile discs.

Findings

These results are quite in good agreement with those found in reality in the brake discs in service and those that may be encountered before in literature research investigations of which these will be very useful for engineers and in the design field in the vehicle brake system industry. These are then compared to experimental results obtained from literatures that measured ventilated discs surface temperatures to validate the accuracy of the results from this simulation model.

Originality/value

The novelty of the work is the application of the FEM to solve the thermomechanical problem in which the results of this analysis are in accordance with the realized and in the current life of the braking phenomenon and in the brake discs in service thus with the thermal gradients and the phenomena of damage observed on used discs brake.

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 26 July 2013

Ali Belhocine and Mostefa Bouchetara

The main purpose of this study is to analyse the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase.

Abstract

Purpose

The main purpose of this study is to analyse the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase.

Design/methodology/approach

The simulation strategy is based on computer code ANSYS11. The modeling of transient temperature in the disc is actually used to identify the factor of geometric design of the disc to install the ventilation system in vehicles. The thermal‐structural analysis is then used coupling to determine the deformation and the Von Mises stress established in the disc, the contact pressure distribution in pads.

Findings

The analysis results showed that temperature field and stress field in the process of braking phase were fully coupled.

Originality/value

The results are satisfactory when compared with those of the specialized literature.

Details

International Journal of Clothing Science and Technology, vol. 25 no. 4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 3 December 2019

Ricardo Andres García-León, Wilder Quintero-Quintero and Magda Rodriguez-Castilla

The braking system on motorcycles is of vital importance, taking into account that its operation is based on the friction between the surfaces in the contact that are found heat…

Abstract

Purpose

The braking system on motorcycles is of vital importance, taking into account that its operation is based on the friction between the surfaces in the contact that are found heat and, therefore, the brake liquid, the thermoelastic deformation on the contact surface, the degradation and failure of the material, as can be attributed to the safety of the occupants. The purpose of this paper is to perform mathematical calculations regarding the phenomena of the transfer of heat generated in the brake system.

Design/methodology/approach

Using SolidWorks simulation software, the geometric model of the three disc brakes of the different cylinders was carried out to identify the elements with the variations of the maximum temperature, and the verification with the calculations was made under ideal condition (80 Km/h and 12°C).

Findings

The results obtained show that with the mathematical calculations it was possible to validate the correct functioning of the braking system under different operating conditions, the systems that have higher capacity of displacement generate higher heat loss at higher speed so that their time of cooling according to Newton is major.

Originality/value

Through the analysis of finite elements, it was possible to identify that the braking system in severe working conditions is not overheated, assuring a natural convection cooling in approximately 12 min according to the mathematical calculations made.

Details

Smart and Sustainable Built Environment, vol. 9 no. 2
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 2 July 2020

Dinesh Shinde, Mukesh Bulsara and K.N. Mistry

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake

Abstract

Purpose

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake friction material (BFM).

Design/methodology/approach

Taguchi method was applied to design an experiment using three different discs of gray cast iron with different surface roughness, which is measured using optical profilometer. These discs were subjected to sliding against pins prepared with the developed non-asbestos BFM, using pin on disc friction and wear monitor.

Findings

The experimental results shows that the disc 2 (Ra = 3.77 µm) gives wear of 22.78 µm and coefficient of friction of 0.462, which is recommended for extreme brake performance. Analysis of Taguchi design revealed that the disc surface was most significant parameter among the parameters under study.

Practical implications

During braking, continuous sliding between the BFM and brake disc or drum not only results into wear of BFM but also changes the surface finish of the brake drum or disc. This leads to variation in surface topography of the drum or disc surface with application of brakes, which further affects the characteristics of the BFM.

Originality/value

The tribological performance of BFM depends upon the topography of the surface on which it was sliding. To get best performance of the non-asbestos friction materials, disc having moderate surface finish is recommended. Scanning electron microscope micrographs had shown the different plateaus formed and energy-dispersive X-ray spectroscopy spectra identified presence of different chemical elements prior to sliding of the pins surface over different discs surface topography.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0120/

Details

Industrial Lubrication and Tribology, vol. 72 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 February 2016

Yan Yin, Xingming Xiao, Jiusheng Bao, Jinge Liu, Yuhao Lu and Yangyang Ji

The purpose of this study is to establish a new temperature set for characterizing the frictional temperature rise (FTR) of disc brakes. The FTR produced by braking is an…

Abstract

Purpose

The purpose of this study is to establish a new temperature set for characterizing the frictional temperature rise (FTR) of disc brakes. The FTR produced by braking is an important factor which directly affects the tribological properties of disc brakes. Presently, most existing researches characterize the FTR only by several static parameters such as average temperature or maximum temperature, which cannot reflect accurately the dynamic characteristics of temperature variation in the process of braking. In this paper, a new temperature parameter set was extracted and the influences of braking conditions on these parameters were investigated by experiments.

Design/methodology/approach

First, several simulated braking experiments of disc brakes were conducted to reveal the dynamic variation rules and mechanisms of the FTR in braking. Second, the characteristic parameter subset of the FTR was extracted with five significant parameters, namely, initial temperature, average temperature, end temperature, maximum temperature and the ratio of maximum temperature time. Furthermore, the fitting parameter subset of the FTR was constructed based on the temperature rise curve. Finally, the influence and mechanisms of initial braking velocity and braking pressure on the new temperature parameter set were investigated through braking experiments.

Findings

This paper extracted a new temperature parameter set including a characteristic parameter subset and a fitting parameter subset and revealed the influences of braking conditions on it by experiments.

Originality/value

The results showed that the new temperature parameter set extracted in this paper can characterize the dynamic characteristics of disc brake’s FTR variations more objectively and comprehensively. The research results will provide a theoretical basis for extracting the fault feature of friction properties.

Details

Industrial Lubrication and Tribology, vol. 68 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

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