METHOD TO DETECT AND REMOVE GAS BUBBLES FROM MOLTEN SUBSTRATE TO PREVENT HOLLOW FIBER FORMATION

摘要

Method and apparatus for removing bubbles from a molten substrate. The molten substrate from a furnace passes through a downtube to reach additional manufacturing tools, such as an extrusion bushing. One or more ultrasonic sensors are arranged along the downtube. The ultrasonic sensor(s) transmit ultrasonic energy into the molten substrate and measure a characteristic of the ultrasonic energy, such as a propagation time for the ultrasonic energy to be reflected back to the ultrasonic sensor(s). A bubble is detected when a change in the characteristic of the ultrasonic energy is detected. When a bubble is detected, flow through the downtube is diverted to a duct to remove a slug of molten substrate that includes the bubble.

主权项

1. An apparatus for supplying a molten substrate, the apparatus comprising:
a downtube adapted to receive the molten substrate at an upstream end of the downtube and to distribute the molten substrate at a downstream end of the downtube; an ultrasonic sensor arranged along the downtube, wherein the ultrasonic sensor is operable to detect bubbles in the molten substrate in the downtube; and a duct arranged along the downtube, wherein the duct is operable to remove a slug of the molten substrate from the downtube upon the ultrasonic sensor detecting a bubble in the molten substrate.