Dynamic And FEM Analysis Of The Winding System Of The Water-jet Slotting-cutting Machine For Outburst Prevention

Coal mine gas control plays an important role in ensuring the safety of production, but suffers various difficulties. The air permeability of some mines is low, and with the working depth increasing, the difficulty of gas drainage and its costs increases threatening the safety of production. There are many traditional ways of dealing with outburst of gas such as detonating in advance, drilling and then hydraulically punching, with all suffering low efficiency and compromised tunneling speed. Theory and practice show that adopting the method of cutting slots from within drill holes using high-pressure water-jet can effectively improve air permeability of the coal mine, thus giving practical significance to developing slot-cutting machines.This thesis’s object of study is the slot-cutting machine that is being modified and improved by Taiyuan University of Technology over the years. The machine is driven by a hydraulic system to wind welded seamless steel tube up onto an expansion cylinder so that a plentiful working radius can be obtained. At the same time, the machine is assisted by running and reversing gears to fulfill each job action and its design goal which is improving air permeability. The welded steel tube which serves as the passageway of the high-pressure water-jet reaches out to the driving working face and is then winded up onto the expansion cylinder when the job is done, therefore is under alternating stress and at risk of fatigue damage. The winding system is the power source of the aforementioned process, under the majority of the load on the machine which makes its transmission performance and its gear train strength focus of research. The major research contents of this thesis include the following few parts:(1) Carry out an in-depth study in the problem of gas outburst in coal-mines and current technologies to prevent it; discuss coal-breaking and gas-outburst-preventing mechanism using high-pressure water jet; on such basis, elaborate on principles and methods of outburst-preventing using high-pressure water-jet;(2) Taking advantage of the powerful function of ANSYS structural analysis module, study the bending static and fatigue of the welded seamless steel tube to predict its life;(3)Using3D-modeling function of UG to obtain models and assembly of the major parts of the machine’s drive system; then using ADAMS to establish rigid-body dynamic model to obtain dynamic simulation results of the drive system.(4) Under the ANSYS environment, study the statics and dynamics of the major parts like gears and the shaft of the drive system to obtain the results of stress, strain,modes of vibration and modals.