Instability Mechanism And Suppress Strategy Of Multi-direction Coupled Vibration Of Hoisting Main Rope Under Disturbance Conditions In Deep Mine Shaft

In the 13 rd Five-Year Plan for Economic and Social Development of the People's Republic of China,it has been pointed out that Risk identification and early warning mechanisms need to be established to proactively release risks in a controlled manner and pace.Emphasis should be put on improving risk prevention and control capabilities in mineral resources and other aspects.The deep mine hoisting system is a rigid-flexible coupling system with characteristics of large stroke,high speed,heavy load,variable mass,strong time-varying and large inertia.A hoisting system is more sensitive to external disturbances.It is easy to generate abnormal vibration and cause a sharp increase in the dynamic load of the wire rope,which deteriorates the operational stability of the hoisting system,and even causes fail and accidents such as broken ropes.It seriously threatens the safe production of coal mines.Therefore,achieving high-speed and smooth operation of deep mine hoisting systems under disturbing conditions is a challenge that must be faced in deep shaft mining.This thesis has carried out research from the following four aspects:(1)Taking the Lebus drum of the ultra-deep mine hoist as the research object,the model of the loop and interlayer transition of the wire rope on the reel is established.Longitudinal-lateral-lateral boundary excitation expression for vibration of the wire end of the drum,hoisting stroke and winding hoisting speed and acceleration are obtained.A transverse-lateral vibration model of the super-deep mine hoisting suspension rope is established.The numerical solution is to obtain the longitudinal forced displacement excitation of the main vertical hoisting rope at the end of the rollerhead sheave caused by the variation of the length of the suspension rope caused by the lateral vibration of the suspension rope space.(2)Longitudinal-horizontal-lateral multi-directional disturbance model of mine hoisting main rope is established.Investigation includes the instability mechanism of the main rope longitudinal vibration under the dynamic excitation of the suspension rope and the change of the rope length and Mechanism of lateral impact instability of main rope and hoisting conveyance caused by misalignment of rigid guide joint.Research indicates: smaller wire rope damping will exacerbate lateral vibrations of hoisting dynamic loads,main ropes and hoisting conveyance;the lateral vibration of the suspension rope has a great influence on the hoisting dynamic load;a large increase of rope length will increase the vibration displacement of the main rope and conveyance;the misalignment of the guide joint has a great influence on the lateral impact acceleration of the hoisting conveyance and the dynamic load of the main rope.(3)Based on balance cylinder and magnetorheological damper,a new suspension device of longitudinal vibration reduction of deep mine hoisting system is designed.The method for calculating and adjusting the suspension stiffness of the new suspension device is given.Based on disc spring and magnetorheological damper,guiding rollers for lateral vibration reduction of deep mine hoisting system is designed and the calculation model of the contact stiffness between theguiding roller and the rigid guide is given.The working principle of two damping devices is expounded,and the calculation model of output damping force is established.Material selection and output damping force calculation are performed,the geometric parameters of the MR damper are determined and the strength of the MR damper is checked.Magnetic circuit of magnetorheological damper is designed,and based on ANSYS Maxwell software,a simulation model of magnetic circuit is established to verify the rationality of magnetic circuit design.(4)Constructed the longitudinal vibration control equation of the ultra-deep mine hoisting system.The research indicates: The magnetorheological damper suspension device can effectively reduce the longitudinal vibration displacement and impact force of the hoisting main rope and the hoisting conveyance and has a good application prospect.The lateral vibration control equation of the ultra-deep mine hoisting system is constructed.The research indicates: under the impact excitation of the rigid guide joint misalignment and vibration reduction of magnetorheological damper guiding roller.The lateral impact vibration displacement of the hoisting container and the main rope can be rapidly attenuated to approach zero and the hoisting dynamic load caused by the lateral vibration of the main rope can also be effectively attenuated.