The rotational molding is a manufacturing method that allows obtaining parts with hollow form by rotating a mold around two perpendicular axes with the part material in the liquid state. Although the manufacturing method was proposed more than one century ago, there are yet aspects less investigated and the emergence of new materials that can be processed by rotational molding also generate interesting problems for the researchers. The paper presents some theoretical considerations concerning the conditions for the liquid flow during the rotational molding process. The coordinates of a point belonging to the mold were derived, even for the case where the mold rotates around two perpendicular axes. By knowing the relations specific to the point motion, the motion speed can be expressed. The main forces acting on a small volume of liquid material, i.e., gravitational, viscous, and centrifugal forces, were taken into consideration. The resultant force ensures conditions for the penetration of the liquid material in the narrow spaces of the mold cavity. A systemic analysis was used to highlight the main input and output factors specific to the process.
|Journal||Proceedings in Manufacturing Systems|
|Publication status||Published - 1 Jan 2012|