The PZ 257 B separating drum with the planetary central adjustment developed by MTF Technik is the best-selling and benchmark among separating drums. It consists of a drum cage with ten pairs of rollers that can be easily adjusted to new part geometries in just a few seconds using a central adjustment mechanism.

Between the roller pairs, this results in 10 separating slots with a continuously adjustable opening width between 3 mm and 53 mm. The length of each separating slot is approximately 700 mm (optionally also 500 mm, 1,000 mm, or 1,200 mm). The rollers are available in PVC, galvanized steel, or stainless steel. Two rollers are connected to each other in pairs via a belt. A further belt is stretched across the entire drum cage, so that when the cage rotates, all rollers turn in opposite directions. This special feature of the MTF design significantly reduces the tendency for parts to jam and considerably improves separation performance compared to rigid rods. The drum cage is loosely mounted on four wheels, one of which serves as a drive wheel powered by a high-torque planetary geared motor. The wheels are housed in a welded base frame lined with anodized aluminum sheets, which guide the smaller parts below the drum cage into containers. Depending on the desired application, the sheets can optionally be made of stainless steel or galvanized sheet metal with various surface finishes. The inlet ring of the drum cage is lined with a screw conveyor made of PVC (optionally also of steel or stainless steel) to dampen the parts as they enter the cage and to convey them safely into the separation area. The material is fed in via a swiveling inlet chute made of anodized aluminum, attached to the base frame. This chute is lined with polyamide for additional noise reduction and part protection (optionally galvanized steel or stainless steel). To separate more than two different fractions, the inlet and/or outlet ring of the drum can be equipped with features such as holes or tubes. This allows for combinations of hole/roller separating drums or tube/roller separating drums. All adjustments to the separating drum, including height, inclination, size of the separating gap, inclination and position of the inlet chute, etc., can be made without tools in seconds. Thus, the separator can be used extremely flexibly and is the first choice, especially for a wide range of parts with many handling processes.