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

2013 ◽  
Vol 37 (4) ◽  
pp. 1161-1175 ◽  
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.

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

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.

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

Wear ◽  
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

Simulation Study of Temperature Field and Stress Field of Disc Brake Based on Direct Coupling Method

2009 ◽  
Vol 628-629 ◽  
pp. 287-292 ◽  
Author(s):  
Xun Yang ◽  
Ji Xin Wang ◽  
J.C. Fan
Keyword(s):  
Temperature Field ◽  
Stress Field ◽  
Material Selection ◽  
Three Dimensional ◽  
Element Model ◽  
Direct Coupling ◽  
Coupling Method ◽  
Disc Brake ◽  
Emergency Braking ◽  
Sequential Coupling

In the process of automobile braking, the interaction between the temperature and the dynamic stress of disc brake is a very complex work. In order to simulate this problem accurately, a three-dimensional finite element model was built. Meanwhile the displacement and thermal boundary conditions for solution were determined, in which the coefficient of convection varies with the transient changing of temperature and time. The distributions of stress field and temperature field of the rotor and pads in an emergency braking were analyzed by the direct coupling method. The results of analysis prove that the thermal-structural direct coupling method can simulate the interaction between the stress field and the temperature field more exactly than the axisymmetric method and sequential coupling method do. The changing of stress field is mainly influenced by the temperature field. The results extracted from coupled simulation can give references for the material selection and structural designs in the development of disc brake.

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

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.

Three-Dimensional Finite Element Study on Effects of Nonlinear Temperature Gradients in Concrete Pavements

1998 ◽  
Vol 1629 (1) ◽  
pp. 58-66 ◽  
Author(s):  
Ivindra Pane ◽  
Will Hansen ◽  
Ashraf R. Mohamed
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Maximum Tensile Stress ◽  
Temperature Gradients ◽  
Fe Model ◽  
Concrete Pavements ◽  
Full Contact ◽  
Nonlinear Temperature ◽  
Loss Of Contact ◽  
Three Dimensional Finite Element

A three-dimensional (3D) finite element (FE) model is developed to investigate whether the condition of plane sections remaining plane exists in concrete pavements subjected to nonlinear temperature gradients. This model is utilized to validate the analytical method proposed by Mohamed and Hansen. The 3D brick element is chosen so that the plane section condition is not imposed in the model, as compared with the model using the flat plate element. Furthermore, the possibility of loss of contact between the pavement slab and the subgrade is studied. The condition of full contact is investigated for a nonlinear temperature gradient that produces the maximum tensile stress in the slab according to the data used. Two slab lengths and two radii of relative stiffness are considered. It is found that plane sections remain plane for the entire slab except for a region very close to the free edges, which also establishes the boundary where solutions by Mohamed and Hansen are applicable. In both cases of the contact condition, the 3D FE model predicts no loss of contact between the slab and the subgrade.

scholarly journals 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 ◽  
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.

Thermal Response Analysis of Barrel of ISAW

2012 ◽  
Vol 468-471 ◽  
pp. 1262-1265
Author(s):  
Yan Jun Zhao ◽  
Qin Man Fan ◽  
Wen Qing Ge ◽  
Cheng Xu
Keyword(s):  
Temperature Field ◽  
Stress Field ◽  
Material Properties ◽  
Research Work ◽  
Three Dimensional ◽  
Thermal Response ◽  
Coupling Model ◽  
Response Analysis ◽  
Fe Model ◽  
The Individual

Aim at Individual Soldier Automatic Weapon (ISAW), three-dimensional FE model and thermoelasticity coupling model of barrel were built. The coupling temperature field and coupling stress field of the barrel were calculated. Laws of the coupling temperature field and coupling stress field were obtained. The coupling temperature field and coupling stress field of different set of barrel aim at automatic fire were compared. The results show that the Material Properties of the barrel is security. Current research work will be helpful the Individual Soldier Automatic weapon design and the life of barrel study.

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