Reciprocating-Screw Unit Blows Sterile Bottles

Uniloy Milacron, Manchester, Mich., has added a controlled-atmosphere model to its series of UMR2000 reciprocating-screw blow molders.

Uniloy Milacron, Manchester, Mich., has added a controlled-atmosphere model to its series of UMR2000 reciprocating-screw blow molders. The UMR2000CB is a “clean blow” design that uses sterile blowing air and an enclosed, pressurized clamp for high-volume production of bacteria-free containers. A stainless-steel air system uses steam purge and HEPA filters to deliver sterile blowing air. A proprietary mechanical sealing device at the end of the blowing cycle seals the containers, trapping sterile air inside the bottles until they are filled. The cam-actuated sealing device is contained within the mold and consists of two pinch bars that seal the top of the bottle. To avoid bottle bulging due to shrinkage, a patented mechanical volume evacuation system presses the sides of the bottle to ensure it attains the proper volume. The machine produces about 60 bottles/hr. The clamp area is also enclosed to maintain a controlled atmosphere. A laminar airflow device mounted on the machine delivers dehumidified air to the clamp interior, producing positive pressure to prevent outside air from leaking in. Uniloy Milacron has sold two 10-cavity models with a 90-mm extruder to a large U.K. dairy for on-site production of 64-oz milk bottles.