What is rotational molding (roto-molding)?
Rotomolding is a manufacturing process for molding plastic parts. It's one of the oldest in plastic's history. Raw material (in our case, powdered polyethylène) is placed in a hollow mould. Made of steel or aluminium, this mold is then closed and heated. Heat makes the plastic melt and allows it to stick onto the mold's interior walls. Meanwhile, the mold sowly rotates around two perpendicular axes to insure even plastic thickness thourgh the part. The mold then goes through a cooling phase during which it continues to rotate. Once cooled to desired temperature, the mold is opened and the molded part removed.