Novel PET water bottle needs no ribs. (Blow Molding).

New modifications to the G66 six-cavity reheat stretch-blow molder from ADS S.A. in Paris, France, make it feasible to produce what is described as the first off-center, rib-free PET bottle for noncarbonated water. Strict wall-thickness control and a bottle design with highly contoured surfaces provide sufficient rigidity without the usual ribs.

Bottles of 0.5,1, and 1.5 liters were designed for Ty Nant, a water packager in Wales, U.K. Bottle seam lines are nearly invisible because they follow the wave-like contours of the bottle. Special care is taken to ensure that the asymmetrical bottle base orients precisely enough to allow proper registration in the labeling equipment.

The modified G66 machine includes specialized cooling to precisely control the wall-thickness profile, as well as stretching devices adapted for specific wall sections where dangers of overstretching are most acute. ADS also developed special devices to optimize heat distribution in the preform oven.

ADS, which hopes to sell machines for making odd-shaped PET bottles in the U.S., also designed and built the 1.5L blow molds. Other mold sizes were made by R&D Tool & Engineering in the U.K. Tel: [phone], e-mail [e-mail]