It’s not often that claims are made of major innovations in blow molding.
At a press conference in New York today, Amcor Rigid Plastics, a leading producer of rigid plastic packaging, and Italy’s Sacmi Imola S.C., a leading manufacturer of compression molding equipment for closures, announced the commercialization of the industry’s first Compression Blow Forming (CBF) machine for the production of rigid HDPE pharmaceutical bottles. The process combines compression molding and blow molding, and is said to deliver significant advantages over conventional processes, including quality, higher productivity, sustainability, and the potential for lightweighting.
Amcor collaborated with Sacmi – the original developer of the process – in a 14-month development project to adapt the unique technology for pharmaceutical packaging. The two companies primarily focused on optimization and implementation of process control enhancements to ensure the new technology platform met the requirements of pharmaceutical manufacturers.
Amcor has an exclusive arrangement with Sacmi to utilize the technology in select market segments and global regions. The company has already commissioned a 12-cavity platform (CBF-12), and is producing HDPE packer (over-the-counter and prescription) bottles at its Youngsville, N.C., facility. Three additional machines are on order and will be in production by the end of the year.
“For the pharmaceutical industry, compression blow forming is one of the most significant technological developments for rigid packaging in decades – it’s a game-changer for an industry that demands risk-free performance,” said Tod Eberle, vice president, quality and engineering, for Amcor Rigid Plastics. “Compression blow forming is the most advanced processing system for the production of pharmaceutical containers, delivering high-quality, reliable, and defect-free parts,” according to Bob Israni, Amcor’s technical manager for the pharmaceutical market.
In compression blow forming, material is extruded, cut, and precisely transferred into a compression cavity. A preform is produced and a pre-blow and full-blow process is completed in the same mold station with no transfer of the preform. Compression blow forming has no manifold for melt distribution to individual separate cavities, which can result in better quality parts because there are no temperature differences and less chance of resin burn and degradation. The process delivers less particulate contamination and due to the continuous extrusion process with simple melt channel, resin and color changes are also quicker.
The pre-blow process allows for effective separation of plastic from the compression core. This reduces the chance of plastic sticking to the metal core rod, resulting in more uniform wall thickness distribution. Weight distribution is also better controlled with compression blow forming. The weight of the resin shot is controlled for all cavities with a servo-controlled melt pump, resulting in more accurate part weight distribution across all mold cavities. The process also operates at lower temperatures, which results in lower residual stress in the end product and cycle times which are reduced.
In addition to the 12-cavity unit already in production, Amcor has committed to additional CBF systems, including a 20 cavity unit which will be in production by the end of 2012. New-generation equipment will have capability for production of HDPE, PP, and PET pharmaceutical containers.