Method of connecting plastic tube to a plastic part

A method of connecting a plastic tube in fluid-tight connection with a plastic member comprising the steps of providing a tube of a plastic which when sufficiently heated in a selected area from the exterior side of the tube expands radially outwardly in that area to form a bulge on the tube, heating predetermined areas of the tube sufficiently from the exterior side thereof to form an outwardly extending bulge on the tube having axially spaced inner facing walls, applying a force on the tube with the walls in heat-softened condition to move the walls toward each other, and thereafter molding a plastic member about a portion of the tube which includes the bulge.

The method of making a medical device having a plastic tube connected in fluid-tight connection with a plastic hub comprising the steps of providing a plastic tube of predetermined length which when heated sufficiently in selected areas from the exterior side of the tube expands radially outwardly in that area to form a bulge, heating predetermined areas of a proximal end portion of the plastic tube sufficiently from the exterior side thereof to form a radially outwardly extending generally annular bulge thereon with the axis of the bulge at an angle to the longitudinal axis of the tube, cooling the tube sufficiently to harden the bulge, inserting the end portion of the plastic tube including the bulge into a hub mold, filling the mold with a plastic material to mold a hub with the plastic material about the bulge, cooling the plastic material of the hub and removing the hub from the mold with the tube bulge embedded in the hub.