Mill rotary body is in its own gravity and remain in the cylinder of the material with steel ball gravity interaction situations, and the bearing contact. Therefore the loading mainly has two parts, one is a rotary body of their own gravity, two cylinder material and steel balls under the action of gravity exerted on the inner wall of the cylinder pressure.

1 the gravity load

As already mentioned, in solid modeling without the establishment of cylinder body and cover of the lining plate, hollow shaft inside the bushing and fixed ring, so in order not to affect the steel ball in calculation, gravity load, need to liner weight according to equivalent density to the cylinder body and the end cover, the hollow shaft the interior of the bushing and fixed ring weight according to equivalent density to the hollow shaft, so as to realize the gravity compensation. Equivalent methods are as follows:

( 1) cylinder body ( including the corresponding liner) weight is 147t, volume is 9.4704m3, so the equivalent density of 15522kg/m3; (the original shell material density is 7850kg/m3 )

( 2) each end cap ( including the corresponding liner) heavy 46.5t, volume is 3.377m3, so the ball equivalent density is 13770kg/m3; (the original cover material density is 7850kg/m3 )

( 3) ( including a fixed ring, hollow shaft bushing for feeding, discharging Bush ) 94t, volume is 6.528m3, so its equivalent density is 14400kg/m3. (the original hollow shaft material density is 7850kg/m3 )

2 Application of node load

Cylinder ball and material can be regarded as some equivalent density body, and that its upper surface is level on the wall of the cylinder, it is pressure proportional to the material layer depth. The steel ball and the weight of the material also can be discretized into corresponding unit area pressure value.

Ball mill in static full load case material and the ball for a total weight of 400t, the bulk specific gravity is 4.5t/m3, we can calculate material depth h = 0.6285m.

In order to barrel imposed change surface load, based on the cylinder body by materials and steel ball role in the region set up a layer of surface effect unit surf154, the unit can be used for a variety of changes in load and surface effect. And then on the surf154 unit applying varying pressure load, the applied pressure value is proportional to the role of regional nodes in the coordinate system (here refers to the Cartesian coordinates ) height. Set material depth is zero node by the pressure is zero, the proportion coefficient is K.