Dynamic brake characteristics of disc brake during emergency braking of the kilometer deep coal 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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Effect of Vibration on Emergency Braking Tribological Behaviors of Brake Shoe of Deep Coal Mine Hoist

Applied Sciences ◽

10.3390/app11146441 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6441

Author(s):

Dagang Wang ◽

Ruixin Wang ◽

Bo Wang ◽

Magd Abdel Wahab

Keyword(s):

Coal Mine ◽

Equivalent Stress ◽

Von Mises Stress ◽

Wear Loss ◽

Brake Disc ◽

Brake Shoe ◽

Emergency Braking ◽

Tribological Behaviors ◽

Deep Coal Mine ◽

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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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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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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Numerical Modeling of Mine Hoist Disc Brake Temperature for Safer Operation

Sustainability ◽

10.3390/su13052874 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2874

Author(s):

Florin Dumitru Popescu ◽

Sorin Mihai Radu ◽

Andrei Andraș ◽

Ildiko Brînaș

Keyword(s):

Raw Materials ◽

Calculation Model ◽

Scale Model ◽

Temperature Threshold ◽

Disc Brake ◽

Emergency Braking ◽

Drive Wheel ◽

Real Material ◽

Cable Drive ◽

Mine Hoist

The sustainable exploitation of raw materials, with improved safety and increased productivity, is closely linked to the development of mechanical mining installations. Mine hoists are designed for the transport of material, equipment and personnel between the mine surface and the underground. The mine hoist braking system is of paramount importance in its safe operation. Thus, for both drum and disc brake systems, the temperature of the friction surfaces is important for ensuring efficient braking, as exceeding the temperature threshold causes a decrease in the braking capacity. In this paper we present a numerical calculation model for the temperature of the braking disc of a mine hoist in the case of emergency braking. A real-scale model was built, based on the cable drive wheel and disc brake system of a hoisting machine used in Romania. Real material characteristics were imposed for the brake discs, the cable drive wheel and the brake pads. The simulation was performed for decelerations of 3, 3.5, 4 and 4.5 m/s2. The analysis shows that regardless of the acceleration and time simulated, the disc temperature reaches its maximum after 1.35 s of emergency braking. This value does not exceed the 327 °C limit where, according to previous studies, the braking power starts to fade. It means that the emergency braking is safe for the acceleration and masses under consideration, in the case of the studied mine hoist.

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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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The Design of Disc Brake for Mine Hoist in Civil Engineering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.568.212 ◽

2012 ◽

Vol 568 ◽

pp. 212-215 ◽

Cited By ~ 1

Author(s):

Hai Tao Zhang ◽

Ying Jun Dai ◽

Yu Jing Jia ◽

Guang Zhen Cheng

Keyword(s):

Salt Spray ◽

Outer Cylinder ◽

Positive Pressure ◽

Brake Disc ◽

Disc Brake ◽

Brake Pads ◽

Disc Brakes ◽

Cylinder Piston ◽

Set Up ◽

Mine Hoist

This article will describe the research status and the features of control system of the disc brakes of mine hoist. The disc brakes consist of body, outer cylinder, cylinder, piston, ring, disc springs, plunger, gate disk and other components. The disc brakes use the pre-load of disc springs to force the piston to move towards the brake disc, push the brake pads out, then the brake pads and drum brake disc contact and resulting in positive pressure, then the formation of friction produce a braking torque. When the brake system loose pads, the cylinder is filled with the pressure oil, which make the piston compresses the disc springs, and promote the brake pads to move back and then left brake disc, remove the braking force. The hydraulic circuit of the braking system chooses two-way parallel oil and four oil cylinder brake. A slip road set up a one-way throttle, making the slip road brake slightly delayed, which will achieve two stage braking and make work more stable. This disc brake is normally closed, which means when the hoist does not work, the brake is in the state of braking to prevent the occurrence of accidents. This brake is safe, reliable and sensitive in action. The materials of brake pads is rigid asbestos plastic, which have stable friction coefficient, good wear resistance, is not sensitive to the aqueous medium and salt spray,it has flexible installation location, and it is easy to use, adjust and maintain.

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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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Numerical Modeling and Simulation Analysis of Temperature Field of Disc Brake on Trains

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.199-200.1492 ◽

2011 ◽

Vol 199-200 ◽

pp. 1492-1495 ◽

Cited By ~ 1

Author(s):

Guo Shun Wang ◽

Rong Fu ◽

Liang Zhao

Keyword(s):

Temperature Field ◽

Temperature Gradient ◽

High Speed ◽

Large Scale ◽

Working Condition ◽

Constant Speed ◽

Brake Disc ◽

Disc Brake ◽

Brake Pad ◽

Finite Element Software

The simulation calculation on the temperature field of the disc brake system on high-speed trains under the working condition of constant speed at 50Km/h is made. A steady-state calculation model is established according to the actual geometric size of a brake disc and a brake pad, and the analog calculation and simulation on the temperature field of the brake disc and the brake pad by using the large-scale nonlinear finite element software ABAQUS are carried out. The distribution rules of the temperature field of the brake disc and the brake pad under the working condition of constant speed are made known. The surface temperature of the brake disc at friction radius is the highest, with a band distribution for temperature. There exists a temperature flex point in the direction of thickness, of which the thickness occupies 15% of that of the brake disc; due to the small volume of the brake pad, the temperature gradient of the whole brake pad is not sharp, and larger temperature gradient occurs only on the contact surface.

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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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