Medical bottle design puts blow molding flash to good use
Creative thinking by Abbot Labs and FGH Systems, Inc. turned wasted blow molding flash into a value-added feature in 1000 and 1500 ml bottles for sterile medical solutions. Their innovative solution t...
Creative thinking by Abbot Labs and FGH Systems, Inc. turned wasted blow molding flash into a value-added feature in 1000 and 1500 ml bottles for sterile medical solutions. Their innovative solution turned the flash on the bottom of polypropylene bottles into a tuckable tab that can be lifted up to allow hanging of the bottle for intravenous use.
The resulting flat bottom allows the bottles to be conveyed standing up for filling.
An alternative to awkward form-fill-seal plastic pouches, the square bottles are easy to handle, provide superior packaging/storage efficiency, and allow dual use versatility — pourable or hangable, says John Lord, principal engineer for Abbott Labs and project manager on the bottling innovation.
FHG Systems, Denville, NJ, developed the mold design and trim mechanism for the Abbott Laboratories bottles and modified a Uniloy Milacron BW6000DE blow molding machine for folding and locking the hanging tab securely into a recess in the bottom of the bottles.
“We made a unit cavity mold for the one liter size and proved out the whole concept here on a lab machine,” said Frank Hohmann, FGH president. “We had to qualify the whole machine with Abbott Labs to very stringent requirements, particularly on neck finish and tuck bottom consistency. If a hang tab popped out and a bottle were to tip over, it could really mess up the conveyor line.”
The trim method conceived by FGH for the hang tab removes flash for the outside shape while a punch knocks out the center hole. A counter plate locates the flash and keeps it from bending or shifting during trim, said Hohmann. FGH also designed the trim tool with air jets to cool off the flash. “When the bottle comes out the mold, the plastic is still hot and gummy, so we apply spot cooling before trimming,” he explains. “All this works together to make sure that flash is positively separated.”
Uniloy Milacron 513-536-2603