Abstract: An extruder assembly comprising a barrel, through which a conductor can travel; a first subassembly for extruding a first sleeve on the conductor; and a second subassembly for extruding a second sleeve onto the first sleeve, the second sleeve comprising a first portion, a second portion, and a cross-section comprising a first annulus sector and a second annulus sector, the first portion comprising the first annulus sector, the second portion comprising the second annulus sector, the first and second portions are in contact with the first sleeve.

Abstract: A polymer extrusion head for forming extruded elements includes a tapered supply section and a one-piece helicoid manifold comprising an entrance cone, a spider element for splitting the flow into multiple streams, a cylindrical transition and flow-turning zone, a flow space for re-mixing the streams, and a conical zone. A conical choke ring surrounds the conical zone. An extrusion tip and die are disposed downstream of the manifold and body. The body and die are provided with heaters, and the manifold and extrusion tip may include internal heaters. The extrusion tip may be accessed for maintenance or changeover to another shape or size. The die surrounding the tip may be readily centered with respect to the tip. An axial surface in the die acts as a seat for the choke ring.