Film Processor Boosts Line Performance with Air-Ring Retrofit
One of Indonesia’s leading processors of high-end flexible packaging films has experiencing significant gains in productivity as a result of upgrading lines with new air rings furnished by Windmoeller & Hoelscher (W&H).
Based in Jakarta, PT Plasindo Lestari was founded in 1986, and currently employs more than 1400 from a 1-million-ft2 plant, making films for food, beverage, home-care and personal-care packaging. The company’s product portfolio includes LLDPE-based barrier films, cast PP and metalized PP and PE in a range of thicknesses. Its operation is integrated to include printing in up to eight colors and inline dry lamination. The company serves both local and multinational brands.
Over the years, PT Plasindo Lestari has installed an undisclosed number of state-of-the-art blown-film lines to help it produce high-end, tight-tolerance products, and also invested in a continued training program for the operators. As a result, most of the films it makes are produced using edge-slitting knives. That way, every extruded pound of material ends up as sellable product on the roll instead of going through a granulation process.
The processor’s most recent upgrade was installed earlier this year on one of the newer W&H Varex five-layer PE lines. The line was already equipped with a high-output air ring—an Arctis HP—producing at high rates for some years, but W&H’s Module Sales Team, which focuses on offering upgrades to existing systems, identified this particular line as a candidate to increase its already high output even further, as well as stabilize production and even improve the film quality.
Says Gerd Kasslemann, who is with W&H’s Line Audit and Retrofit Solutions unit,, “In our technical center the activities to push existing limits never stop. As part of that process, if we find a new and more powerful air-ring solution, we start to identify possible customers that might benefit from retrofitting this new technology to their existing lines. This happens parallel to using that technology on brand-new lines. So, we approached PT Plasindo Lestari and informed them about what the projected improvement would look like. Naturally, they were open to getting more than 10% extra output right away, and so we prepared the upgrade kit for them.”
PT Plasido Lestari realized output gains up to 23% by upgrading a W&H Varex line with a new air ring.
Quality is critical in the demanding applications PT Plasindo Lestari serves. Every pound of material it extrudes ends up as sellable product on the roll instead of going through a granulation process.
Adds Timothy Cahyadi, COO PT Plasindo Lestari, “We have already used the expertise of the W&H Module Sales team and upgraded one of our non-W&H blown-film lines with a W&H P2K profile-controlled air ring. This turned out very well for our production. We have a number of fairly new Varex machines, and W&H approached us with the idea to improve our production numbers even further on one of them. People at W&H were pretty sure to make this work, but before we bought the upgrade, we challenged them to come into the plant and prove it first.”
A W&H technician visited the processor’s plant and started to fine-tune the line “as is” to establish an output benchmark. After restarting the machine with the new air ring—an Arctis XP—running the same structure, an improvement in bubble stability was obvious right away, making it clear that output could be increased further with the bubble still holding rock steady.
“It feels like the bubble is kept in a kind of circular vise.”
During the days that followed, three of PT Plasindo Lestari’s most prominent products were tested on the upgraded line. As Kassleman notes, not every product reacted the same way—output improvements ranged from 12% to 23%. And as Kassleman points out, this was accomplished on a line that was state-of-the-art just three years ago. “Retrofitting such technology to older lines is expected to provide even higher increases,” he adds.
Notes Cahyadi, “We were surprised and excited when the line was restarted. But the output increase tells only half of the story. When running at a higher rate, the new air ring delivers even better width and gauge uniformity, and the whole production is running more consistently. It feels like the bubble is kept in a kind of circular vise. Even the night-shift operators manage to do quick changeovers without losing the bubble.”
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