Fatigue Analysis And Life Prediction Of Shearers’ Torque Shaft

The shearers’ torque shaft is usually designed as the weakest link of the drivingsystem in actual working conditions to reduce the loss caused by the driving systemdamage in the worst working conditions, which plays a role in protecting motors andmain driving. The torque shaft introduced in this paper is from shearers produced by onecoal machinery company. In the practical production of coalmine, the motor’s shaft isoften damaged because of the unreasonable design and unresponsive fracture of torqueshaft. Then the torque shaft is modified and can be used for overload protection, butbecause of its short working life and unregular fracture plane, the shearers’ performancecan’t yet be worked out.In order to solve the above-mentioned problems, the3D models of shearers’ torqueshafts are established by using the3D design and analysis software. Based on thesemodels, static analysis and fatigue analysis of the torque shaft are accomplished and thedistribution nephograms of torque shaft’s stress, strain, safety coefficient, damagepercentage and life cycle are obtained. Through analyzing, the disadvantages and theircauses of the designed torque shaft are found out. Aiming at these disadvantages, animproved design scheme of torque shaft is proposed based on fracture mechanics theory.In this scheme, the unload groove’s cut shape of torque shaft is modified. Comparativeanalysis of different cut-shape torque shaft pre and post modification is accomplished,which compares the advantage and disadvantage of the two kinds of torque shafts andverifies the improved scheme’s rationality. These work provide the basis for parametricdesign and research of torque shaft in the future.