The Addex Manual Gauge Control Air Ring is based upon our Dual Lip Air Ring that has been the standard for the blown film industry worldwide.

The MGC permits selective adjustment to correct film gauge deviation caused by extruder, die, or ambient anomalies by as much as 25% (several customers have achieved a 50% reduction).

Depending on die size, the MGC is equipped with anywhere from 100 to 304 individually adjustable control bolts in 10mm (3/8”) wide air vanes, providing high resolution, yet requiring only average operator skills. Because it is manually operated, its price is only a fraction of an automatic system. Making gauge corrections with the MGC can best be compared to adjusting die bolts to make up for uneven film  thickness distribution.

A spot is marked on the film bubble, indicating its orientation, the gauge of the film sample with the marking is measured off line and plotted, and the relative adjusting bolts on the MGC are turned in or out to make corrections. The magnitude of correction per bolt turn can also be determined by before and after film measurements. Although the MGC lends itself to use with stationary as well as oscillating/rotating dies, the latter can control only about half the gauge deviations. In addition to the MGC, Addex also manufactures a fully automatic External Gauge Control system (EGC), and an automatic Internal Gauge Control system (IGC).

Internal Gauge Control

FEATURES The system uses the air gaps of two Internal Bubble Cooling Pancakes to control the variations in film thickness. The lower pancake with sliding teeth does the bulk of the gauge correction at the melt’s exit from the die, where the film is most susceptible to thickness changes due to cooling. The second toothed pancake improves the already drastic corrections made by the first one.

The Very High Resolution of the control comes from:

● the multitude of the only 1/8" (3mm) wide teeth that can be moved to any up or down position within the 1/4" (6mm) air gap;

● the proximity (approximately 1/2" (12mm) of the bubble to the pancake’s air gap, which allows for very little diffusion of the controlling air.