The service life of the 仕切りダイヤフラム (including the grate plates) in a tube mill is generally about 10 months. Its life is primarily determined by the wear resistance of the cast material. In practice, however, apart from this important factor, the service life of the most severely worn areas of the diaphragm also governs the overall life of the diaphragm, yet the area of these most severely worn regions accounts for only a relatively small proportion of the total diaphragm area. It is indeed unreasonable to replace an entire diaphragm just because localised areas have worn out more rapidly.

To address this problem, the thickness of the mildly worn areas should be appropriately reduced, while the thickness of the severely worn areas should be suitably increased. By adopting this approach, the mass of the diaphragm increases only slightly compared with the original, but its service life can be greatly extended. The performance of the modified diaphragm is presented in Table 2.9.

Table 2.9 Performance of the modified diaphragm