Reduce production downtime for structures from the simplest sheet to complex packaging films by simplifying the fine-tuning of layer thicknesses with the Ultraflow V feedblock for flat-die coextrusion. The coextrusion feedblock has adjustable “combining planes” located where the melt streams join the central flow channel. These combining planes can operate in two modes, each with a different advantage in terms of ease and adjustability:
Eliminate feedblock adjustment by the operator. By leaving the adjustable plane in free-floating mode, operators can let the position be determined directly by the equilibrium pressure developed by flow from the extruders. The combining plane responds to the pressures of the different mass flows from the extruder by achieving a state of equilibrium reflecting these differences. In this way, a change in flow from one of the extruders causes a readjustment of the combining plane at the point where materials merge.
Optimize layer-to-layer interfaces. For polymers whose interaction at the point of confluence poses the possibility of disrupting or compromising the multilayer structure, the adjustable plane can be moved manually to fine-tune polymer flow. Shafts extending from outside the feedblock into the centers of the adjustable planes provide ease of operation. Simple settings will change the adjustable planes from free-floating mode to varying levels of responsiveness to melt flow pressure. Once adjusted, an adjustable plane remains in a fixed position.