陆上风力发电机齿轮箱回油管开裂原因OA

After 2 years of operation of a large onshore wind turbine,the oil return pipe of the gearbox cracked.By means of macroscopic observation,chemical composition analysis,metallographic examination,mechanical property test and scanning electron microscope analysis,the causes of the cracking of the oil return pipe were analyzed,and the improvement measures were put forward.The results show that the improper control of the production process of the cracked tubing bellows led to the problems of the bellows,such as 32%thinner wall thickness,5.5 times of effective stiffness deviation,welding defects and stress concentration.The above multi-factor coupling effect greatly weakened the service performance of the bellows.Under the action of external cyclic load,the top of the welded fusion zone of the bellows of the wind turbine connecting parts initiated the crack source first due to stress concentration,and finally caused fatigue cracking.