From the below scheme you can see two different type of plates, smooth and ondulated.
The ondulated plates are suitable for grinded bodies in alumina; and the smooth plates are suitable for lining with grinded bodies in silica.
In the following images you can see a solution find from the technical office to improve the productive capacity of a mill 061, in this case the increase has been of a 14%: the technical staff re-studied the diaphragm and the head of the mill unloading.