PROCESS FOR CONTROLLING THE MANUFACTURING OF DIMENSIONALLY VARYING TUBULAR MEMBERS

摘要

A system for controlling the manufacture of dimensionally varying tubular members extrudes a continuous tube with a lumen from an extrusion machine. The extrusion machine has a melt pump, which regulates the flow rate of the melt through the extrusion head. The extrusion head forms a melt flow and introduces air pressure within the melt flow to form the lumen of the tubing. An air pressure regulator controls the pressure of the air introduced through the extrusion head. A puller supplies tension to the tubing as it is extruded through the extrusion head. The system uses a diameter gage and/or a wall thickness gage to measure the change in the wall thickness of the tubing as a function of its length. Further, the system uses a laser to gage the profile of the tubing. The system automatically compares the measured dimensions against stored dimension targets to generate feedback to the components of the extrusion machine, automatically adjusting one or more process variables for the next tubular member in the extrusion sequence. Finally, the system sorts the tubular members that fall within acceptable error margins, and sorts out those that fall outside the error margins.