| With the development of belt conveyor toward large-scale direction, thetensioning device is characterized by mechanical and electrical integration ofliquid technology of automatic. There will be in danger of fire with mineral oilas hydraulic transmission medium, and which is a huge security risk for the coalmine equipment. High water-based emulsion has been widely used in thecoalmine equipment such as hydraulic pressure supports, due to the advantagesof good flame retardant. It is necessary to study how to replace the hydraulic oilwith emulsion for hydraulic transmission medium of belt conveyor tensioningdevice.First of all, design theory of belt conveyor tensioning device is analyzed, thetensioning force were calculated with a3.2km telescopic belt conveyor as adesign example. For emulsion medium leakage and short lifetime of emulsionhydro-motor, Based on principles of reduce the system pressure and reduce theworking time of emulsion hydro-motor as possible, the overall scheme ofhydraulic tensioning system with emulsion for belt conveyor was formed. Based on simulation software AMESim, under the precondition of hydraulictensioning device with emulsion is used, the tension of two side of driving drumand take-up are analyzed in process of extensible belt conveyor is starting andthe tail is moving, the velocity, tension and displacement are analyzed，theinfluence of conveyor belt parameters and coulomb friction and viscous frictionforce on dynamic characteristics of extensible belt conveyor are analyzed, anddraw the following conclusions:The flow rate of Pump station must be greater than400L/min to meet therequirements; When the winch is starting and braking，The tension of loose sideof driving drum and take-up is volatility. Unlike the moving trolley and looseside of driving drum, the fluctuation of tight side tension is bigger when the tailis moving. The maximal displacement of moving trolley is8.1m, occurred in thetime of belt conveyor is going to finish starting, and the maximum speed is0.18m/s. When the tensioning device is designed, the moving of tail and the beltconveyor startup mode should be fully taken into account, no matter the processof conveyor start-up or the tail moving, full load condition are the mostunfavorable conditions.When extensible belt conveyor is starting, tension of tight side of drivingdrum, tensioning force ratio, the displacement of moving trolley were positivelycorrelation with load weight; Elastic wave propagation velocity is negativelyrelated to the load volume; When tail is moving, the greater the load quantity,the smaller tension fluctuation of moving trolley. Elastic wave propagation speed along the conveyor belt, velocity of tighttension rising conveyor is starting, the fluctuation of tension of tight side whentail is moving were positively correlation with conveyor belt elastic modulus.The maximal displacement of moving trolley is negatively correlated withconveyor belt elastic modulus. Peak tension of tight side of driving drum hasnothing to do with the conveyor belt elastic modulus. The greater conveyor beltrheological constants, the more impact of tension of cushion.The greater the proportion of the viscous friction, the peak tension of tightside of driving drum is smaller, the tension is more stable, the smaller thefluctuation of tail conveyor belt velocity. |
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