Ball Mill Trunnion

The four spots were located approximately 90 degrees apart. The trunnion thickness where the erosion occurred was approximately 7 inches before the erosion began. In order to perform the repair the thin, eroded sections had to be removed. In order to minimize the amount of parent material removed and maximize the effectiveness of the repair it was necessary to install intermediate inserts that would fill in the majority of the erosion, and provide a backing for the external insert that would be installed into the trunnion’s surface. The inside surface of these intermediate inserts was machined so that there would be metal to metal contact between them and the inner sleeve. Once the inserts were installed into the cavity they were attached to the trunnion by means of the Metalocks and Metalace. Once all of the inserts were installed the inner diameter of the trunnion and the backs of the inserts were machined for the installation of the inner sleeve. Once the intermediate inserts were installed the final fit of the external inserts could be completed. Once the outer insert was fitted, the Metalocks and Metalace were installed along the perimeter. These components formed the mechanical connection between the trunnion and the insert inner and outer inserts.