In-line drawing of tubular film in second bubble, includes a stabilizing ring at exit from heater that follows first bubble

摘要

Biaxially oriented tubular film (3) produced by blow extrusion followed by reheating in a heater (5) and drawing in a second bubble (7). At the exit from the heater (5) is a stabilizing ring (50), which can be fitted with a temperature sensor (52) to assist in controlling the heater temperature. The distance (A) of the ring (50) from the heater exit can be adjusted with an actuator (53).