Extruder makers B&P Process Equipment and Systems LLC and Milacron Inc. celebrated their year-old partnership - and turned out enough wood-plastic composite boards to build a deck - at a Sept. 28 open house at B&P headquarters in Saginaw.
``I think it's going to be very good for both of us,'' said B&P President and Chief Executive Officer Ray Miller.
Milacron, which claims to be the largest supplier of extruders to the wood-plastic market, builds parallel and conical extruders, both of which use counter-rotating screws. B&P brings to the partnership its corotating experience, with a machine marketed by Milacron under the TimberEx, or TE brand.
TE machines bear the names of both companies. The corotating TE machines provide high-volume production of 1,000-8,000 pounds an hour, which is ideal for deck boards, according to Tom Brown, Milacron director of sales and marketing and product manager.
Milacron has sold more than 280 extruders for running plastic decking and profiles from wood flour and other natural fibers, Brown said. But the Cincinnati-based company does not make corotating extruders.
So Milacron and B&P announced their agreement in mid-2005.
``B&P has the name in the market for corotating technology, and Milacron has the name out there, obviously, in the wood-composite industry,'' Brown said. ``That's why we searched for a partner, because the corotating technology is significantly different than the counter-rotating technology. So for us to get into it, we'd have to have a whole different engineering staff and a whole different group of support people.''
Corotating extruders use segmented screws and barrels. They are used in plastics compounding, but also in a range of industries including chemicals and powder coatings. During the open house, B&P employees were finishing up a huge continuous kneader to turn out carbon anode paste, a raw material used in the production of aluminum.
Despite that diversity, Miller and Brown stressed the co-branded extruders were developed specially for the wood-plastic market.
Miller said B&P already was working on the technology before the partnership, running not only wood flour, the most popular material, but also checking out other natural fibers such as straw and hemp.
Brown said it's important to supply the appropriate technology for each customer. ``We're not blind to the fact that there are other corotating twin-screws out there in the market, but what we wanted to do is not just take a compounding twin-screw and apply it to the wood-composite market. We wanted to have a twin-screw profile extruder,'' he said.
At the open house, the companies ran redwood-colored deck board on a TE50 laboratory line and displayed a TE125. The numbers refer to the inside barrel-bore dimension, measured in millimeters.
The lab line was equipped with two side feeders and a die from Strandex Corp. of Madison, Wis. The decking came out into a Conair water cooling bath.
The TE125 machine can extrude up to 4,000 pounds an hour.
All the TE machines feature B&P's patented, direct-discharge technology, which eliminates the need for a gear pump or a separate, single-screw extruder to build up pressure. In the last segment area, near end of the screw, B&P reduces both the size of the bore and the outside diameter of the screw flights. In effect, it splits into two separate, single-screw chambers.
Brown said traditional corotating extruders tend to push the material off to one side, going through the die. But the reduced-bore design builds the pressure and pumps more efficiently, so the wood-plastic mix is pumped evenly across the entire die.
Cutting out the need for the extra gear pump and extruder makes for a simpler machine that uses less energy, according to B&P and Milacron.
``Pound for pound, we supply a piece of equipment that does what other people do, for a lot less money,'' Miller said.
Repair and replacement costs also are reduced, because individual screw and barrel segments can be removed in the area of wear. Another benefit is optimized free volume for medium-torque and heat-sensitive applications.
Impressive output is a big attraction for corotating machines. The peak output of 8,000 pounds per hour for the largest size, TE160, does tend to grab the attention of deck board manufacturers.
But corotating technology is about more than high output. The machine is more versatile than counter-rotating or conical extruders when it comes to materials. ``It can run pellets. It can run reactor flake. It can run powder. It can run regrind. It can run two different, dissimilar materials,'' Brown said.
The TE extruder line uses an Eisenbeiss Speed Star gearbox.
