Strength Analysis of Wind Turbine Rotor Lifting Tool

Lifting the rotor assembly is one of the significant stages in the wind turbine erection steps. In order to design a safe lifting tool, the strength analysis of the rotor lifting tool has been conducted in the present study. Entirely ۳۷ bolts (ISO ۴۰۱۷ M۴۲x۱۷۰.۱ steel grade B hexagon head) have been employed to contact the rotor assembly to the lifting tool. Based on the grade of the bolts and frictional coefficient, tightening preload and torque have been calculated. The lifting process has been separated into six steps and stress analysis has been conducted in each step. Steel C۶۰EQT has been used for ۱ section and steel S۳۵۵ has been utilized for the other parts. The present investigation demonstrates the lowest design safety factor occurs in step one of the lifting process. The lowest safety factor is ۳.۹۴ and ۳.۷۵ for section ۱ and other parts respectively. At the end of the design process, we can state the design safety factor of ۳.۷۵ for the rotor lifting tool could be acceptable.

Keywords:

Wind turbine Lifting tool , Rotor assembly , Stress analysis , Finite element method