Design rules for rotomolded parts
Rotational Molding of Industrial Parts with Polymer Materials

If the polymer covers the walls during the rotational movements, almost all shapes may be achieved. However, for the design of a rotomolded part, it is necessary to respect the following rules :

• the internal surface is free which may induce variations in the wall thickness of the part. This variation strongly depends on the complexity of the geometry. For a given geometry, it is necessary to optimize the temperature and the rotation velocity of the two main axes to obtain a homogeneous thickness ;

• sharp edges represent obstacles to the flow of molten polymer and powder. They must be avoided (figure  33 ) ;

• rotational molding creates some special effects (figure