Failure Analysis on Bearing Thrust Plate of an Extruder

The bearing thrust plate of an extruder fractured after servicing for only several months. Means such as macro examination, chemical compositions analysis, hardness test, metallographic examination and scanning electron microscope observation were used to study the failure reason of the thrust plate. The results show that contact fatigue with subsurface spalling and cracks, caused by overloads, is responsible for the fracture of the thrust plate, and high operation pressure and improper assembly contributed to the overloads.