Abstract: In a process of manufacturing shaped elements from synthetic thermoplastics, particularly polyolefins, such as polyethylene and polypropylene, wherein the plastic material is heated to a temperature above its softening temperature and is shaped in that state to form the shaped element and is subsequently cooled to a temperature below its softening temperature, the shaped elements are shaped in a hot state to form intermediate products having a certain oversize over the desired final dimensions and after they have been cooled are caused by a material-compacting pressing operation to assume the desired final dimensions, in which they are dimensionally stable.