Munich, Germany-Krauss-Maffei says its new polyurethane mixing head, "is extremely precise and reliable, even at the lowest throughput rates."
Some PU uses need, "a mixing head capable of high-precision processing at very low throughput rates," said the Munich-headquartered group.
Excellent mixing performance, even at lowest throughputs, is crucial for getting the best products, as is "very smooth, laminar flow pour," the machinery maker added.
Krauss-Maffei claims its new mini-volume MK 3,5/5UL-2KVV mixing head (pictured) meets these specifications reliably down to 5g/s throughput.
The machinery designer said potential applications for this new device include pouring PU seals or adhesives, production of filter foams and ultra-high quality surface coatings in processes such as clear coat moulding or SkinForm.
So small are the mixing head components that the control piston (3.5 mm diameter) and the cleaning piston (5 mm diameter) are made of high-performance materials with specially treated surfaces, Krauss-Maffei points out. And in spite of these tiny dimensions, they still contain recirculation grooves, the company said.
Features include a compact design for easy handling, and the ability to operate in inaccessible areas. Components are fed to the mix head via a connector block with an integrated high-pressure filter, which also provides a by-pass function to help set-up and production start.
The mix head is self-cleaning, with a discharge tube at 90° to the mixing chamber, to reduce turbulence.
In addition, this design makes it possible to throttle the flow from the mixing head to improve the homogeneity of hard-to-mix compounds, Krauss-Maffei said. "