Specialty German injection press maker Ettlinger Kunststoffmaschinen GmbH is expanding into filters for recycled plastic, but the ERF is not just any filter.
ERF, which stands for Ettlinger Rotation Filter, can remove as much as 18 percent of the aluminum from polypropylene regrind. Not that many end products actually have 18 percent aluminum; the company from KÃ¶nigsbrunn just uses that for a worst-case scenario. But one product that the ERF has worked its magic on is construction walls that use layers of PP and aluminum, owner Roderich Ettlinger said at Fakuma, held Oct. 15-18 in Friedrichshafen.
The firm has lots of experience working with recycled plastic. One of its key markets, molders of pallets, consumes lots of waste plastic. Ettlinger said pallets often contain recycled household polyethylene and PP, old plastic crates for toting beer and soft drinks and even plastic pipe.
Ettlinger founded his company in 1983. With just a dozen employees and sales of 4 million euros ($4.5 million), the company designs custom-made machines for each job and does final assembly, while outsourcing the actual machining operations.
To compete against the injection press giants, Ettlinger focuses on special machines to make parts that are very small and precise or very large, like pallets, according to engineer Axel Jung.
The biggest Ettlinger presses boast a shot size of 220 pounds and a clamping force of 3,300 tons, using a low-pressure technology.
``We are a very small company, but all over the world we have machines,'' Ettlinger said. The company's pallet expertise has spread its reputation, through installed machines in Europe, the United States, Canada, Japan, Africa and even Uzbekistan.
Ettlinger said the new filter should give his company a wider appeal, to any company that has a tough recycling job.
Here is how the filter works: After scrap is ground, it goes through a normal, vented extruder. The melt that comes out of the extruder moves through a rotating filter, made of a special hardened stainless steel with laser-cut holes in the outside drum. The waste then goes through a stripper device, rotating in the opposite direction of the screw, which removes the waste to a carryout screw.
Each turn of the filter cartridge results in a complete cleaning of the filter area, the company said.
Once cleaned, the plastic goes to a standard extruder and through a strand pelletizer.