Research On Key Rotator Dynamic Characteristics Of Friction Mine Hoist

The key rotators (main shaft, drum and sheave wheel) are the hub of the frictionmine hoist. Their dynamic characteristics are closely related to the healthy state of themine hoist. When the shaft is bent or unbalance, the associated component get looseand the rolling bearing fails, abnormal vibration energy and frequency of main shaftwill come into being. Therefore, the state of the main shaft can be diagnosed bystudies into the vibration characteristics. The drum stress mainly contains pressure onthe shell from the hoisting conveyance through wire ropes and the shear force on thespoke plate from the electromotor torque through main shaft. The drum stresscharacteristics can be effectively used to monitor the load of the mine hoist. Thesheave rotation angle is well linearly related to the passing length of the wire rope andhence can be used to detect the slipping. The thesis is supported by the NationalHigh-tech Research and Development Projects “Intelligent Diagnosis of MalignantAccident of Mine Hoist”, National Natural Science Foundation of China “HealthyMonitoring of Super Deep Vertical Shaft Hoist System based on WSN”. The keyrotators (main shaft, drum and sheave wheel) of the friction mine hoist is studied withthe reliable condition monitoring of the hoist as the target. The studies on the dynamiccharactoristics of the main shaft vibration, the drum spoke plate stress and the sheavewheel rotation are carried out. The key dynamic parameters of the vibrationacceleration of the main shaft bearing housing, the drum spoke plate stress and therotation angle of the sheave wheel are analyzed. Research results will provide theorytheoretical support and technological means for the fault diagnosis of the main shaftof the friction mine hoist, warning of the abnormal lifting load and monitoring of theslipping, which can and improve the reliability of mine hoist monitoring.First, the vibration spectrum of the main shaft under the bending or unbalance ofthe main shaft, loose of the associated component and faults in the rolling bearings areanslysed and the vibration characteristics of the friction hoist during run-up areemphasized. The vibration frequencies of the main shaft are studied based on theenergy growth rate of the vibration energy and the correlation of the multispeedmultiple frequency. Besides, diagnosis of the rolling bearing faults and decoupling ofthe aliased spectrum verify that energy growth rate and multispeed multiple frequencycorrelation can be applied to the main shaft vibration analysis. Second, the properties of the radial and tangential forces for the drum of thefriction mine hoist are analyzed. Based on the stress and lifting load parameters of thespoke plate for the drum and combining the RBF neural network, the correlationmodel between the stress of the drum spoke plate and the lifting load is establishedand based on the correlation model, the warning model of the abnormal lifting load isbuilt.Third, considering the rotation angles of the fixed wheel and the floating wheelsshould be detected respectively, a new detection device of rotation angle for thesheave wheel is designed to avoid being out of sync of the fixed wheel and thefloating wheels. A model of the slipping state for the friction mine hoist based on thesheave wheel rotation angle is built to monitor the normal slippling, serious slippingand discordance of the fixed wheel and the floating wheels.Finally, detections of the vibration acceleration of the bearing housing for themain shaft and the rotation angle of the drum are analyzed. The rotator’s multi-pointwireless stress collection method is proposed for the needs of the stress detection forthe spoke plate. Based on the wireless sensor network, virtual instruments andnetwork sharing, we developed the spoke plate stress detection system of the drumwhich achieves wireless collection, local monitoring and remote sharing and isverified to be feasible and reliable by field testing.