Method of fabricating vacuum sizing apparatus

Abstract

A vacuum sizing apparatus is positioned downstream from an extruder along a path followed by a body of thermoplastics material as the body exudes in a heated, deformable state from the extruder. The apparatus includes structure defining an elongate sizing surface extending along the path of travel of the body. A multiplicity of vacuum channels are formed in the structure and open through the sizing surface for drawing outer wall portions of the body into conforming engagement with the sizing surface as the wall portions cool and rigidify while moving along the sizing surface. The structure includes a plurality of side-by-side structural segments, each of which defines a portion of the sizing surface, adjacent ones of which have mating side walls. The vacuum channels are of small cross section and are formed as grooves milled or ground in the side walls of the segments. A clamping system releasably clamps the segments together and permits their disassembly to provide access to the vacuum channels for cleaning.

Dependencies are inferred from the claim text.