Abstract:
In view of the fact that deep mining has gradually become the normal state of coal resources development in China, as the "throat" connecting the ground and underground, the mine hoisting equipment will develop in the direction of ultra-deepening and large-scale, and the winding hoist with multi-rope and multi-layer structure will gradually become the best choice for deep coal mining. However, mineral dust is easy to adhere to the surface of hoisting wire rope with lubricating protection, thus affecting the normal lubricating state of wire rope, and then interfering with its winding contact process on the drum. Additionally, the longitudinal vibration is inevitable due to the time-varying length of hoisting wire rope and the fluctuation of acceleration during service, which has an impact on the friction and wear performance between winding contact wire ropes. Therefore, exploring the influence of mineral dust on the vibration-worn characteristics of winding hoisting wire rope can provide the theoretical support for the operation and maintenance of the mine hoisting system serving in the environment of harsh dust. The vibration-worn test platform of wire rope was designed and built firstly in this thesis according to the winding contact form of mine hoisting wire rope. Then, taking the two kinds of mineral dusts, coal particle and ore particle, which were commonly found in mine, as examples, the vibration-worn tests of winding hoisting wire ropes with different particle parameters (concentration and size of particle) were carried out with the help of the platform, and the evolution of tribological parameters of wire rope was analyzed. Finally, the interference mechanism of two kinds of mineral dusts on the hoisting wire rope was obtained according to the surface wear morphology and element content of wire rope. The results showed that the average friction coefficient of wire rope increased from 0.158 to 0.173 in the relatively stable stage with the increase of volume fraction of coal particle from 10% to 40%, while the increase of size of particle made it show an opposite change trend, and the change trend of maximum temperature rise in the wind-out region of wire rope corresponded to its friction coefficient and fluctuates within 3 ℃ basically. The wear depth of wire rope increased to 117.7 μm with the volume fraction of coal particle increasing to 40%, while the size of particle had little influence on the wear. In addition, the content of C element on the worn surface of wire rope was increasing, the adhesion effect was becoming more and more seriously, and the delamination phenomenon was becoming more and more obviously with the increasing volume fraction of coal particle. Therefore, a certain amount of coal particles mixed into the lubricating grease would have a negative impact on the lubricating state between winding contact wire ropes, accelerating their wear, and the concentration of particle had a greater impact. For ore particle, the friction coefficient of wire rope increased to 0.157 and the wear depth increased to 120.4 µm with the volume fraction gradually increasing to 40%, and the curve of friction coefficient of wire rope was smoother than that for coal particle, while the size of particle was negatively correlated with the friction coefficient and the wear depth. The maximum temperature rose of wire rope in the wind-out region under the interference of ore particle mainly fluctuates within 2 ℃. Moreover, the increase of concentration and the decrease of size of ore particle led to more serious abrasive wear on the contact surface of wire rope. Therefore, the ore particle mixed with lubricating grease would destroy the lubricating state between winding contact wire ropes and accelerate their surface cutting wear.