Nozzle plate holder

In combination with an apparatus for the extrusion of a molten thermoplastic polymer including a nozzle plate arranged perpendicularly to the axial direction of flow of the polymer melt therethrough, an improved holding means for said nozzle plate comprising:

• a housing having side walls enclosing an axially extending cavity, said housing having a feed opening into said cavity at its inlet end to receive said polymer melt for extrusion and a discharge opening at its opposite end, the discharge opening of said housing being open to axially insert said nozzle along the inner wall surface formed by the sides of the housing;
• a peripheral groove extending around the inner wall surface of said housing at an axially spaced interval from the discharge end thereof;
• a plurality of supporting ledge elements removably inserted into said peripheral groove in end-to-end proximity and extending completely around the inner periphery of said side walls, the radially innermost ends of said ledge elements projecting out of the groove and into the discharge opening of said housing as a bearing surface to support said nozzle plate when fully inserted in said housing;
• and
• a sealing ring removably inserted between the nozzle plate and said bearing surface of the ledge elements to support and to seal the nozzle plate against the pressure exerted axially by the melt on the nozzle plate in the discharge direction.