Vibration Test and Fault Diagnosis for Main Hoist Gearbox of Heavy Casting Crane

In view of the structure and running characteristics of gearbox of large and special crane, we have respectively carried out vibration test of fault and free-fault gearbox containing planetary gear in the work. With the help of Matlab engineering software, we can read and process the collected vibration signal of gearbox and draw the time-domain and frequency-domain graph. Through the comparative analysis of vibration information of gearboxes, we can determine the link between fault type and signal characteristic value, effectively realize the fault diagnosis of gearbox.

Based on the Online Monitoring and Fault Diagnosis System of the Main Hoist for Mine

According to the reality, an online monitoring and fault diagnosis system of the main hoist for Mine was designed in this article. The system adopts the signal acquisition and processing, fault diagnosis, Web visualization, network real-time database and other related technologies, Real-time monitoring the current, voltage, temperature, speed, vibration and other parameters of the main elevators to Achieve the goals that Increasing efficiency by downsizing, protecting the safe operation of equipment, reducing the maintenance costs.

On the Use of Main Hoist Tension Measurement for Feed Forward in DP Systems During Offshore Installations

DP systems are nowadays widely used on installation and crane vessels. In recent years a few cases have been reported where the DP system becomes instable during the installation. Two main reasons can cause these instabilities. First of all the predictor model that is used in the Kalman filter has to accommodate the difference in the mass that occurs when its weight shifts from the barge to the crane. The second and more important reason is the tension in the main hoist wire which acts as an additional spring in the horizontal plane. Some DP-systems have a special heavy lift mode, which is activated when instabilities occur. The present paper describes a different method that uses the actual tension measurement in the hoist wire to enhance the DP system and correct for the additional forces in the horizontal plane due to the hoisting wire. The proposed method is investigated in a series of model tests and results are presented. It is shown that the hoist feed forward improves the overall behavior significantly.