NEWS
Enercon’s (Menomonee Falls, WI) Induction Sealing Hall of Fame inducted GlaxoSmithKline Consumer Healthcare’s (London) Tums bottle as one of five inaugural members at Pack Expo 2007. The Hall of Fame recognizes induction-sealing challenges that were overcome, including oval-shaped foils, snap-on caps, large and eccentric shapes, metal containers with nontorqued caps, cap and bottle profiles with large air gaps on the sides and top of the induction seal, varying land area tolerances, and sealing two caps of differing height with one induction sealer.
The Tums’ bottle entry featured an oval-shaped foil, which creates a challenge because induction sealing eddy currents travel in a circular path. In addition, its snap-on cap does not provide enough pressure on the inducted foil to create a seal.
Enercon’s Super Seal induction cap sealer with special sealing tunnel directs the induction field across the oval foil for in-line production. Its snap-on cap features a thicker pulpboard insert that applies sufficient pressure on the foil for sealing.
“Enercon’s Induction Sealing Application Engineering team is passionate about solving every application we are asked to seal. With new container shapes and sizes in development, or even other induction-sealing projects, we take our knowledge of past projects, trials, and developments and apply them to finding a solution. Chances are there isn’t any application we haven’t seen. And if there is, we’re up for the challenge,” says Ron May, vice president, engineering, in a news release.
The Tums package is considered an engineering breakthrough because it is believed to be the first oval-shaped bottle to receive an induction seal with a snap-on cap,
Enercon reports.
Prior to the product’s redesign, SmithKline Beecham used conduction sealing for Tums products; however, the conduction machinery had a large footprint and required grueling maintenance.
“The conduction units took up a lot of space, and they were hard to service,” says Jim Pitassi, SmithKline packaging engineer, in a news release. “The maintenance guys had to crawl around them to make necessary changes.”
The new Tums packaging features an oval-shaped neck on a rectangular bottle, similar to the rectangular shape of its Tums predecessors.
Induction sealing, however, traditionally seals only containers with round openings. The machines’ eddy induction currents usually travel in a circular motion, making adaptation to other shapes complicated. Enercon customized its Compak induction sealing system with a sealing head that generates an ovular induction field that seals the redesigned Tums opening.
Enercon and SmithKline then had to design the seal of the snap-on cap. Unlike most induction seals, which use screw caps that apply even pressure, the Tums bottle’s design made creating an adequate seal difficult.
The new cap design employs four locking lugs that hold the 3.3-mm foam-foil-PP liner firmly, creating a solid seal.
This new process also increases efficiency of the line, says Mickey Miramonti, SmithKline supervisor of mechanical services, in a news release.
“There is less downtime, which saves on manpower. And we produce less scrap. The conduction sealers punched the seals on the line, leaving waste, and they didn’t always center the seal on the opening of the bottle, resulting in lost product. Dwell time for the conduction sealers was a rate-limiting factor on-line, so an additional conveyor belt was snaked to slow down the bottles for sealing.”
