The multiple possibilities of multi-layer

Thirty-year-old Haremar Plastics Manufacturing Ltd. (Weston, Ont.) is building on its traditional market of trash liners by venturing into a market that is virtually untapped by Canadian companies: multi-layer blown film.

The enabling technology for this new initiative came together quickly last summer. An old film line was pulled out in April, and a new three-layer line from Battenfeld Gloucester was up and running in August. Mark Lichtblau, corporate vice-president of Haremar, reports with pride that saleable film was rolling off the line 48 hours later.

But the smooth start-up really only hints at the potential of this highly integrated line, says Lichtblau. After four months of production, “we’re still getting acquainted with it, and pushing the line more and more. We’re getting used to the capabilities of all the different features, such as the oscillating nip.”

Haremar has 10 film lines, some with co-extrusion capability. Multi-layer coextrusion is a natural fit. “Our specialty for thirty years was trash liners. For the past five years, we’ve been producing higher quality products for overwrap, bakery film and shrink film,” says Lichtblau. “We developed good communication and service skills in the demanding consumer/retail market, with customers such as Wal-Mart and Loblaws.

“We found the industrial market was underserviced. Our communication skills and ability to deliver product on-time, on-spec is greatly appreciated by this market.”

Flexible line permits diverse products

To produce the higher value laminates and converted films, Haremar purchased an 84 in., three-layer blown film system with three Contracool extruders and a three-layer, 16-in. Internal Bubble Cooling die and feedblock combination from Battenfeld Gloucester. An existing Battenfeld winder was integrated with the new line.

“We have several coextrusion lines for two-layer constructions, but the new line allowed us to upgrade to three layers, and at the same time, it is much faster and more precise,” says Lichtblau.

According to Carl Johnson, product manager of blown film systems for Battenfeld Gloucester, “Haremar wanted to put the best of all available worlds into its system. This particular package gives Haremar a definite flexibility advantage.” The three-layer line is capable of producing a diversity of products, from very thin to very thick films. The die and feedblock combination provides an exceptional range in layer-to-layer percentages or thickness, so Haremar is able to process a wide range of product structures.

Other components from Gloucester are Extec screen changers, Digisonic IBC layflat control system, bubble cage, an 84-in. Traversanip oscillating haul-off, an 84-in. secondary nip assembly and an edge guide assembly.

Haremar completed the blown film line with screws from American Kuhne and a materials handling system from Process Control Corp.

“The resin blending system from Process Control is an incredible system. It’s all based on augers, and the precision is second to none,” Lichtblau comments. He did consider batch gravimetric blending, but concluded the focus on batch consistency was not optimal for the blown film process. With a continuous gravimetric system, says Lichtblau, the blend always contains the right proportions, because the materials are constantly being fed by augers in the correct proportion.

Single control integrates diverse components

The entire Battenfeld system, plus components from other manufacturers, was integrated into a single point of control with Battenfeld Gloucester’s Extrol 6032 microprocessor control unit.

Lichtblau says the process control system was purchased with the employees in mind. “It lets them manage the whole line from one location. And the quality of information we get from the control is remarkable.”

The Extrol integrated line control system controls everything from resin handling through the extrusion process, web process, gauging and gravimetric handling and feeding. Operators are able to access and view real-time, critical line information, including raw material inventory levels, the number of rolls made, footage on a roll, and shift reports.

Haremar also opted for remote access to the process control system, provided through Battenfeld Gloucester’s Extrol Anywhere feature. It gives Haremar the capability to remotely access and communicate with the control from anywhere using an ordinary PC and modem.

“I know this praise sounds excessive, but the Extrol Anywhere feature is really unbelievable,” says Lichtblau. It was particularly useful during start-up and training when only a few key people were fully trained on the new line, and those key people couldn’t always be on hand at the plant, explains Lichtblau.

“I would sometimes get a call at home from an operator, questioning an alarm status perhaps. I’d dial up on my laptop, read the alarms, monitor the system, then walk the operator through the steps to correct the situation. I wouldn’t recommend you make any changes to the line remotely, but it’s a great tool to walk an operator through a problem situation. It enhances communication, and that can only improve your operation.”