At its Monroe plant Costco uses thermoforming equipment and semi-automatic sealing machinery from Sencorp (www.sencorp-inc.com)
The custom in-line sealing machine operates at rates around 15 cycles/min. It has five automated pick-and-place stations and one to six operator stations for product filling. The sealer’s placement sequence before sealing is as follows: front SBS card E-flute pad front blister product back blister and lastly rear SBS card.
Crucial to the packaging was the sealing of the SBS cards to each other. Plant general manager Scott Carnie compares the process to sealing insulation together.
“Most adhesives failed miserably” he states. Carnie says other materials combinations fall apart in short order—even before the packaged products leave the building.
This construction also secures the blister and product and reduces stress seal failure and bent cards associated with packaging heavier products Carnie says.
The front and back blister cards use a specific adhesive that works well with this type of sealing. The development “changed the whole concept of heat sealing” Carnie claims. “There are a number of tricks to do this and though the methods and materials are straightforward it’s an advantage over our competition.”