Heat-shrink tubing process apparatus and method of making heat-shrink tubing

摘要

A continuous heat-shrink tubing process is described having an expansion element disposed with the tubing and a position maintenance feature to keep the expansion element in a desired location. The expansion element may be maintained in a position by pressurized fluid trapped within the tubing between the expansion element and pinch rollers. The pinch roller may be moved to reduce the volume within the section of tubing between the pinch roller nip and the expansion element, and thereby increase the pressure of the trapped fluid. In another embodiment, the expansion element may be held in place by an extruder connector. In yet another embodiment, the expansion element incorporates a magnetic component, or has at least one magnet, or magnetic metals and one or more magnets are configured to maintain an expansion element position through attractive or repulsive magnetic forces.