Abstract:
An extrusion device includes a sculpted extrusion die (100) comprising a pair of mating die lips (108, 110) having sculpted surfaces (118,120) and defining a die exit (112) for an extrudate. The contour of the sculpted surfaces (118, 120) is substantially similar to the contour of a juxtaposed surface (210) configured for receiving the extrudate from the die exit (112) of the sculpted extrusion die (210). The sculpted extrusion die preferably comprises a die lip adjustment mechanism (122) for adjusting a thickness of the extrudate exiting the die exit (112) and the thickness of the extrudate received on the juxtaposed surface (210). The air gap between the die exit (112) of the sculpted extrusion die and the juxtaposed surface (210) preferably is substantially eliminated by adjusting the distance between the sculpted surfaces (118,120) and the juxtaposed surface (210). A method of adjusting a thickness of a substantially continuous sheet of extrudate formed using an embodiment of the sculpted extrusion die (210) is also provided.
Abstract:
An apparatus for the extrusion of a multi-layer parison comprises an extrusion blow molding head having a bore passing through the head with a diverter sleeve located within the bore. There is a first manifold in fluid communication with a first die inlet, and a second manifold in communication with a second die inlet. The first and second manifold substantially surround the diverter sleeve, wherein the first manifold is in fluid communication with a proximal end of a flow path formed by the diverter sleeve and the bore and the second manifold is in fluid communication with the flow path at a first location downstream from the proximal end of the flow path Lands having vanable width are positioned between the manifolds and the flow path. The manifolds and lands are sized so that a polymer melt is maintained in laminar flow through the flow path.