Finite-element stress analysis of end-cover rupture for home-made DTM 350/600 type ball mills has been carried out by using high accurate three dimensional unit. The results show that the phenomenon of larger stress concentration had occurred on sudden variating cross-section at the transit round-corner location of this type of ball mill’s end-cover

leading to occurrence of fracture on the said end-cover

and the fracture accelerates to expand under effect of greater amplitude alternating stress untill rupture of the said end-cover. Some improving measures

such as increasing the round-corner radius at location of contacting hollow shaft with the said transit round-corner etc.

have also been suggested.