APPARATUS FOR MAKING FLEXIBLE TUBING WITH ANNULAR CORRUGATIONS

摘要

Apparatus for making flexible tubing with annular corrugations and uniform wall thickness. The apparatus includes a tubular cylindrical mandrel adapted to receive a sleeve of extruded rubber, and an axially extensible external form adapted to be received over the mandrel and sleeve. The form includes a plurality of axially spaced disk-like elements, each having a circular opening coaxial with the respective circular openings of the other elements, and a plurality of resilient extensible helical springs spaced about the axis of the openings. Each spring is connected to each disk-like element to support the elements in uniformly spaced parallel relation to one another to accommodate generally uniform increase in the axial spacing between said elements when the springs are axially extended. The mandrel has radial ports so that the sleeve may be expanded by internal pressure to make a preliminary impression in the uncured rubber caused by the edges of the circular openings of the disk-like elements.