A melt distribution block for feeding melt through an extrusion die to an extrusion
passage. The melt distribution block has a generally annular body with inner, outer,
front and rear faces. The front and rear faces include a series of flow divider
channels therein extending generally radially inwardly from an inlet and terminating
in a plurality of feed spirals. The feed spirals curve radially inwardly from the
flow divider channels to encircle the inner face and narrow toward a radially inwardly
disposed end. The feed spirals on the front and rear spaces curve in respectively
opposite directions. An inlet port extends into the outer face and fluidly communicates
with the inlet of the flow divider channels. A melt distribution die includes an
axially stacked array of melt distribution blocks interspersed with separator blocks
extending radially about a centrally disposed mandrel to define an extrusion and
passage therebetween.
