Effect of Vibration on Emergency Braking Tribological Behaviors of Brake Shoe of Deep Coal Mine Hoist

The effects of vibration on the emergency braking tribological behaviors of the brake shoe of a deep coal mine hoist were investigated in this study. The thermal, frictional and mechanical parameters of the brake shoe were obtained. The vibration characteristics of the brake shoe during emergency braking were investigated, employing multibody dynamics analysis. The effect of vibration on the emergency braking tribological behaviors (temperature and stress distributions) of brake interfaces was explored using the finite element method. The self-made tribo-brake test rig of a brake shoe was employed to reveal the friction deterioration behaviors of the brake shoe during emergency braking. The results show obvious vibrations of all brake shoes along the direction of positive braking pressure during emergency braking. The vibration causes increases in the equivalent Von Mises stress and temperature at the contact interfaces between the brake disc and the brake shoe as compared to the case of ignoring the vibration. Along the rotation direction of the brake disc, the equivalent stress and temperature of the brake disc surface present three overall rapid increases, as well as two slight decreases during emergency braking. As compared to cyclic emergency braking, continuous emergency braking exhibits more obvious tribological degradation of the brake shoe, attributed to enhanced vibration. The wear loss of the brake shoe increases with increasing emergency braking cycles and continuous emergency braking time.

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Dynamic brake characteristics of disc brake during emergency braking of the kilometer deep coal mine hoist

Advances in Mechanical Engineering ◽

10.1177/1687814020918097 ◽

2020 ◽

Vol 12 (5) ◽

pp. 168781402091809

Author(s):

Dagang Wang ◽

Ruixin Wang ◽

Jun Zhang

Keyword(s):

Effective Mass ◽

Coal Mine ◽

Equivalent Stress ◽

Brake Disc ◽

Disc Brake ◽

Brake Shoe ◽

Brake Torque ◽

Emergency Braking ◽

Deep Coal Mine ◽

Mine Hoist

Dynamic brake characteristics of disc brake during emergency braking of the kilometer deep coal mine hoist were investigated in the present study. The theoretical model of dynamic brake torque of disc brake during emergency braking was given to explore dynamic brake torque properties of disc brake. The three-dimensional thermo-mechanical coupled finite element model of brake disc–brake shoe was established to explore thermo-mechanical characteristics of disc brake during emergency braking. Effects of effective mass, hoisting acceleration and deceleration, and maximum hoisting speed on dynamic brake torques, equivalent von Mises stress, and temperature fields of disc brake during emergency braking were presented. The results show that the evolutions of brake torque, equivalent stress, and temperature of disc brake present fluctuating characteristics. The dynamic brake torque shows the largest change amplitude during emergency braking in the hoisting stage of constant speed. The largest equivalent stress and temperature are both located near the third brake shoe along the rotational direction at each side. An increase in effective mass causes overall decreases in the peak values of brake torque, equivalent stress, and temperature during emergency braking. Increases in hoisting acceleration/deceleration and maximum hoisting speed cause the increases in the maximum equivalent stress and temperature during emergency braking as compared to the slight decrease in the maximum brake torque.

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Preparation of high friction brake shoe material and its tribological behaviors during emergency braking in ultra-deep coal mine hoist

Wear ◽

10.1016/j.wear.2020.203391 ◽

2020 ◽

Vol 458-459 ◽

pp. 203391

Author(s):

Dagang Wang ◽

Jikun Yin ◽

Zhencai Zhu ◽

Dekun Zhang ◽

Dahua Liu ◽

...

Keyword(s):

Coal Mine ◽

Brake Shoe ◽

Emergency Braking ◽

Tribological Behaviors ◽

Deep Coal Mine ◽

Mine Hoist ◽

Friction Brake

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Tribo-Brake Characteristics between Brake Disc and Brake Shoe during Emergency Braking of Deep Coal Mine Hoist with the High Speed and Heavy Load

Energies ◽

10.3390/en13195094 ◽

2020 ◽

Vol 13 (19) ◽

pp. 5094

Author(s):

Dagang Wang ◽

Ruixin Wang ◽

Tong Heng ◽

Guozheng Xie ◽

Dekun Zhang

Keyword(s):

Coal Mine ◽

High Speed ◽

Brake Disc ◽

Disc Brake ◽

Heavy Load ◽

Brake Shoe ◽

Emergency Braking ◽

Deep Coal Mine ◽

Friction Disc ◽

Mine Hoist

The friction wear and thermal fatigue cracking of the brake shoe and friction-induced self-excited vibration (frictional flutter) of the disc brake can easily occur during emergency braking of a deep coal mine hoist with at high speed and with a heavy load. Therefore, tribo-brake characteristics between the brake disc and brake shoe during emergency braking of a deep coal mine hoist are investigated in the present study. Scaled parameters of the disc brake of a deep coal mine hoist are determined by employing the similarity principle. Friction tests between friction disc and brake shoe are carried out to obtain the coefficient of friction in the case of high speed and large specific pressure between the friction disc and brake shoe. Coupled thermo-mechanical finite element analyses of the brake disc and brake shoe are established to investigate temperature and stress fields of the brake disc and brake shoe during emergency braking, which is validated by the engineering failure case. Effects of braking parameters on flutter characteristics between the brake disc and brake shoe are explored by employing a double-degrees-of-freedom vibration mechanism model. The results show that the maximum temperature, equivalent Von Mises stress and contact pressure are all located at the average friction radii of contact surfaces of the brake disc and brake shoe during emergency braking. The cage crashing accident in the case of high speed and heavy load in a typical coal mine shows crack marks and discontinuous burn marks at central locations of brake shoe and brake disc surfaces, respectively, which indicates frictional flutter characteristics between brake disc and brake shoe. During emergency braking, flutter time duration decreases with increasing initial braking speed and damping parameter; the flutter amplitude and frequency of the disc brake increases with increasing normal braking load and stiffness, respectively.

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TRANSIENT THERMO-STRESS FIELD OF BRAKE SHOE DURING MINE HOIST EMERGENCY BRAKING

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2013-0098 ◽

2013 ◽

Vol 37 (4) ◽

pp. 1161-1175 ◽

Cited By ~ 1

Author(s):

Zhen C. Zhu ◽

Wan Ma ◽

Yu X. Peng ◽

Guo A. Chen ◽

Bin B. Liu

Keyword(s):

Stress Field ◽

Friction Surface ◽

Numerical Solutions ◽

Three Dimensional ◽

Temperature Gradients ◽

Fe Model ◽

Brake Shoe ◽

Emergency Braking ◽

Friction Tester ◽

Mine Hoist

In this paper, the finite element (FE) model of the three-dimensional (3-D) transient thermo-stress field of a brake shoe was established and then the software ANSYS 13.0 was used to get the numerical solutions; an experiment was carried out on the X-DM friction tester to verify the FE model. It was found that both the whole temperature and the equivalent stresses of the brake shoe increased and then decreased during mine hoist emergency braking; region of 1 to 3 mm below the friction surface was suffered to larger temperature gradients and stresses.

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Three-dimensional transient temperature field of brake shoe during hoist’s emergency braking

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2008.04.022 ◽

2009 ◽

Vol 29 (5-6) ◽

pp. 932-937 ◽

Cited By ~ 27

Author(s):

Zhen-cai Zhu ◽

Yu-xing Peng ◽

Zhi-yuan Shi ◽

Guo-an Chen

Keyword(s):

Temperature Field ◽

Three Dimensional ◽

Transient Temperature ◽

Brake Shoe ◽

Emergency Braking ◽

Transient Temperature Field

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Energy Consumption Analysis of Level Circulating Cooling System in Sanhejian Deep Coal Mine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.516 ◽

2011 ◽

Vol 396-398 ◽

pp. 516-519

Author(s):

Yi Zhang ◽

Dong Ming Guo ◽

Li Meng

Keyword(s):

Energy Consumption ◽

Coal Mine ◽

Cooling System ◽

Cooling Water ◽

Deep Mining ◽

Heat Damage ◽

Deep Coal Mine ◽

Energy Consumption Analysis ◽

Process System ◽

Technical Issues

With the deep mining in coal mine, heat damage is one of the technical issues need to be solved. HEMS cooling system in Sanhejian Coal Mine is a process system for high-temperature heat damage controlling in deep coal mine, in which cool energy extracted to reduce work face’s ambient temperature to achieve heat damage controlling. Part of the cool energy is from the level circulating of cooling water in -700 level main raodway, the other is from the mine water. We analyze the energy consumption of every subsystem during operation of the HEMS system, which could provide a theoretical basis and technical guidance on more efficiently running of cooling system deep in the future.

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