Whether you’re a film converter, printer or a bag and pouch maker, your processes churn out more than salable product. Web processes also generate static charge, an invisible but influential force that can result in contamination, coating or ink defects, jams, scrap...and headaches.
Static charge is often created when a dielectric material is quickly separated from another surface-like unwinding a roll of film-or after coming in contact with another different material and then separated-such as running a web over rollers. Generally speaking, as production speeds increase, so, too, does the generation and accumulation of static charge.
Little can be done to stop the creation of static charge, but with a variety of solutions constructively placed on your operation, plenty can be done to control static charge and its unwanted affects.
SOLUTIONSne approach to dissipating static charges on the web uses simple, inexpensive grounded tinsel or static control string positioned closely to, or even lightly contacting, the web to dispel the charge or collect contaminants. Of course, neither tinsel nor string requires external power: Ion generation in the electric field on the web and the grounded points of the tinsel or static string are key to this method’s success. However, these passive products require regular replacement as they wear out or become matted with time. Further, tinsel and static string may be ineffective at eliminating the lowest of static charges.
More recently, “active” solutions, in the form of pin array ionizers or electrical static bars, have entered the converting market. Using a high voltage power source, these products generate ions using a series of sharp pins or “emitters.” As Jay Perry, marketing manager for Simco Industrial Static Control explains, recent trends in flexible packaging converting necessitate more active approaches to static elimination.
“One trend that’s shaping packaging and converting today is the economy and improving efficiencies,” says Perry. “As we move to more high-end processes including more sophistication, automation and higher speeds, total static control systems need to follow this trend and do more with less.”
The first active static neutralizer technology required bars to be placed within inches of the web and left users with questions like, "How do I know its on?" Perry explains that Simco’s newest offering, PerforMAX IQ, addresses the drawbacks of earlier static control systems.
“Ideal for unwind and rewind rolls, the PerforMAX IQ works at a greater distance-30 inches-to provide greater efficiencies,” says Perry. The system ensures complete control through self-diagnostic performance features as well as closed-loop, continuous downstream monitoring of static charges on the web.
Like Simco’s product, the IonStorm XR2 system from TAKK Industries provides long range ionization up to 36 inches and includes a powerful controller for high-caliber static elimination. As Terrance Clark, sales manager at TAKK explains, static control manufacturers aren’t doing much to change the way electricity is converted to ions, but rather, the focus is on intuitive interfaces and matching production line automation.
“There’s no question that today’s processes are focused on maximizing throughput,” says Clark. “As today’s machinery focuses on throughput, we’ve focused our attention on automation and user-friendly controls, including a control panel that features remote operation, plus audible or visual indicators as part of a diagnostics panel.”
TAKK’s Model 3750 power controller includes user settings for frequency, voltage and polarity outputs, allowing users to dial in the specific ionization performance required. The unit provides an operation error alarm indicator, rocker on/off switch, illuminated ion pulse rate and an integrated DIN connection for remote control and diagnostics.
At NPE 2009 in June, Meech International unveiled its 977CM Pulsed DC controller, incorporating several features that make it easier for the user to sustain optimum performance and extend the time between static bar cleanings.
“The high voltage of static elimination bars attracts airborne contaminants, meaning previous units would have to be cleaned regularly to remain efficient,” says Matt Fyffe, vice president and general manager. “The new 977CM system has the ability to continuously monitor output from the ionizing bars and will automatically adjust the voltage input to compensate for the contamination.” Once this compensation reaches a predetermined level (for example, an increase of 25%), audible, visible and remote alarm signals alert the operator or plant manager.
Static charge can present itself in many aspects of the converting process, but between passive solutions, active add-ons and even machine adjustments and maintenance, you’ve got a countermeasure in virtually every corner.