Drives from mixer systems Two drive shafts, one above the other, drive a screw pump which mixes the plastic. Several pumps are arranged behind each other. The pumps have different speeds. The plastic is conveyed from one screw pump into the other and thus mixed. This mixing process is done under high temperatures. These temperatures are transferred from the pumps to the drive shafts of the gearbox. The bearings must be designed accordingly. Through a specially driven pressurized oil system the bearing points and the gear meshing are supplied with cooled oil. Compact design combined with different gear ratios set closely together in a very small installation space.