Resumo

CASANOVA, FERNANDO  e  CORONADO, JOHN JAIRO. FAILURE INVESTIGATION OF THE GEAR SHAFT CONNECTED TO A DOUBLE-SCREW EXTRUDER. Dyna rev.fac.nac.minas [online]. 2010, vol.77, n.164, pp. 88-97. ISSN 0012-7353.

Failure analysis of a gear-shaft of a gear-box was conducted. The gear-box is connected to an extruder which is used in the production of bioriented polypropylene. The shaft fractured in a key slot next to a change section zone. Hardness and tension tests, microstructural analysis and scanning electron microscopy (SEM) were carried out on the fractured material. Besides, finite element modeling to obtain the stress state and analysis of fatigue life of the shaft was realized. We concluded that the cause of failure was fatigue, due to the high content of non-metallic inclusions of manganese sulfide in the material resulting in a decrease of the fatigue resistance of the shaft.

Palavras-chave : Gear shaft; failure analysis; inclusions; fatigue.