The manufacturing industry continues to pivot toward automated capabilities, especially as companies grapple with the ongoing workforce crisis. In order to ensure customers receive their labels at record speed and with the highest quality, converters require cutting-edge equipment. Among the necessities: slitter-rewinders.

The slitter-rewinder provides converting of large rolls of labels or flexible packaging, which are typically produced on a digital or flexo printing press, into smaller rolls as quickly and accurately as possible. While the need for speed is ever greater, so too is accuracy. If there are any missteps in this process, the waste – both in terms of time and money – can be devastating.

“Smaller rolls are required so the labels can be applied to finished product, either by hand or an automatic label applicator at high speed. It is very important that rolls that come off the slitter-rewinder are fully inspected, with proper tensions, and are defect-free,” says Joe Caparello, regional sales manager, Rotoflex.

While the process might sound simple in layman’s terms, there are numerous considerations for slitter-rewinders. “Starting with loading a roll of typically-printed material and webbing the machine, it is very important to set up the machine with the right parameters,” states Chiara Prati, CEO and CSO, Prati Company. “These depend on roll sizes, finished roll sizes, substrate specs, finished roll width, etc. As the web goes through the machine, it might be inspected with a camera or a workflow link connected to a press, which will stop the web at a correction table and bad labels or printed material can be removed and/or replaced. The most critical part of a slitter-rewinder is the slitting section. The knives used must ensure a clean cut on the finished roll edges, and must not deflect the web passing through the machine in any way.”

When walking the show floor at Labelexpo Americas, numerous converters marveled at the automated enhancements to the industry’s latest converting equipment. In the four years between this event, the equipment’s evolution was palpable.

One such new product is the updated Omega SRI label finishing system from A B Graphic International (ABG). Delivering high performance slitting, rewinding and inspection, the new model offers a range of enhanced, adjustable options to meet future requirements. With a larger unwind diameter at 830 mm and increased nip roller wraparound, waste is reduced and tension control improved, preventing slippage and interweaving of the web, providing greater versatility.

“Automation plays a large roll in today’s modern slitting equipment,” notes Caparello. “In the early years, setup and inspection were all manual and time-consuming, reducing throughput. Today, in our competitive market, time is money and margins are decreasing, so reducing setup time allows converters to recoup some labor costs with quick setup and automation.”

According to Grafotronic, there are two major benefits of automation in this converting segment. For starters, the automated web tensioning system allows the operator to focus on processing. Secondly, the automation of print quality control processes makes the inspection process independent of human unreliability. Taking the human element out of the equation translates to a quicker and more reliable process.

“We specialize not only in automating the press to continue running nonstop, but also in giving operators some of the best ergonomic advantages in machine operation, for example automatic roll unloading of the rewind,” states Gavin Rittmeyer, VP of sales and marketing, Martin Automatic. “This feature allows the operator freedom to continue tasks with the press without having to be present during the roll transfer or even the sequence of unloading the roll from the rewind spindle.”

Automation also promotes improved customer service functionality. For example, Prati Remote Training Support and Remote Control System allow customers to stay in touch with Prati, guiding them step-by-step with the help of an experienced in-house technology team. Prati can provide ongoing training of its machines after the installation, startup and initial training of a new machine have taken place.

Automation is not only good for efficiency but also for curbing the industry trend of attracting and retaining skilled employees. “Finding skilled operators continues to be a challenge for converters,” says Caparello. “Automation of processes like slitting, print inspection and roll finishing has supported the reduction of operator interaction. By continuing to automate processes such as these, training new personnel is not as in-depth as it may have been in the past.”

“All these solutions allow us to quickly train operators to work on the machine,” adds Morten Toksværd, business development director, Grafotronic. “We no longer must rely only on specialized personnel, but we can easily secure our own staff and eliminate the risk of downtime in the event of staffing problems. Many of our customers have our digital converting equipment already and the software for our slitter-rewinders is exactly the same, therefore allowing managers to cross-train personnel.”

LemuGroup has developed a wide range of converting equipment, which includes the GTU Converter. The equipment features numerous capabilities, from diecutting and perforation to slitting and a contact matrix stripping system.

“The LemuGroup has become the global answer to these and other production issues, which can all be solved by our GTU high-speed converting equipment, glueless turret rewinders and end-of-line boxing and automation,” explains Andre Beaudoin, head of North American sales and marketing. “We now deliver proven robotic automation roll label packaging systems that are curing the lacking manpower issues in the industry. These systems can be purchased as turnkey single operator systems or interfaced with existing press or converting systems currently in production in the plant.

“We have eliminated the need for multiple people standing around doing nothing or slowing down line speeds so people can keep up with the press,” continues Beaudoin. “These people can be redeployed elsewhere in the facility,” he adds. “Lemu’s systems are all digitally equipped with memory retention for repeat work and instantaneous job setups.”

“The goal of automation is always to give operators more freedom to perform higher value-added tasks while increasing productivity and saving resources,” adds Rittmeyer. “With the ongoing shortage of labor and material and increasing costs of material and other inputs, saving time and material continues to gain importance. Converters continue to look more closely at roll automation and ergonomics to give their operators greater freedom and flexibility.”

Now featuring

Slitter-rewinders, much like many of their equipment counterparts on a shop floor, have seen vast improvements over the years. The ultimate goal is to simplify the process for operators, allowing labels to move seamlessly throughout the supply chain.

ABG’s Omega SRI features a host of upgraded features, which include a lower splice table. This allows operators greater flexibility and increased ergonomic comfort, thereby improving productivity and efficiency.

The same holds true for Grafotronic. “Our Hi3 inspection slitter-rewinder is designed to be an operator-friendly machine with a 23.6″ (600 mm) long inspection area,” says Grafotronic’s Toksværd. “This provides a clear view and very fast and easy replacement of faulty or damaged labels. The buffer allows for safe deceleration of the web, eliminating web breaks that cause unnecessary down time and inefficiencies.”

The HI3 machine also has several other functions that support and facilitate the operator’s work. For example, it features an automatically lifted unwinding shaft, web advancer systems that feed the ends of the material on the rewinder and most importantly, automatic setting of circular shear knives, which Grafotronic calls its “Sci-Fi Knives.”

“This solution shortens shear knife setup from 5-10 minutes to seconds by automatically setting up shear knives in seconds,” adds Toksværd. “Customers find that this greatly increases efficiencies and makes for an easy transition to a new operator.”

“Material science and consumer product companies continue to challenge converters with opportunities to find new and better ways to convert thinner materials, multi-laminate materials, linerless and other webs that transcend conventional label converting methods,” adds Martin Automatic’s Rittmeyer. “Thinner, more delicate materials require idler roller technology or bearing technology that allows for high frequency response to changing web and other process conditions without wrinkling or damaging the web in other ways.”

Prati has developed its knife technology, as well. The company utilizes self-sharpening slitting knives that can be adjusted depending on substrate specs. Prati machines can also be upgraded with a FastCut system, which automatically sets the slitting knives into the right position and at the right pressure to the counter knives.

According to Rotoflex, setups have gotten much quicker in recent years. For example, Rotoflex cartridge slitting systems allow knives to be pre-set for the next job, allowing operators a plug-and-play scenario resulting in almost no downtime.

“Tension control systems have improved drastically, from being controlled by clutches and brakes to now being managed by servo motors, giving more consistent performance,” explains Rotoflex’s Caparello. “Also, job save and recall has ensured more consistent product delivery to the customer.”

Inspection

Inspection also plays a critical role in the purchase and installation of slitter-rewinders. Print quality and accuracy are more critical now than ever before, putting a significant amount of emphasis on inspection.

As Chiara Prati notes, almost all slitting-rewinding machines need some sort of inspection. “Good and consistent quality is nowadays a given and cannot be compromised. This occurs with a camera directly installed on the machine or through a workflow system to an inspection system on press. Unless blank labels are produced, print quality cannot just rely on a set of human eyes anymore.”

“Inspection is the most important process to reduce the risk of customer complaints,” explains Grafotronic’s Toksværd. “Unfortunately, the most unreliable part of this process is usually the human factor. Thanks to the use of automatic inspection systems, we minimize the impact of this factor. Camera inspection makes the operator’s work less stressful and increases productivity throughout the shift. It also reduces the risk of complaints to an absolute minimum. In both cases, it increases the company’s profitability. We work with all of the major inspection brands, and this gives our customers the flexibility that they expect from Grafotronic.”

“Previously, manual inspection of labels was done with a strobe light, leaving room for operator error and resulting in defective labels being shipped to customers, complaints received, and possibly even lost business,” comments Rotoflex’s Caparello. “Automated inspection systems compare print images to a ‘master image’ and place the highlighted error in front of the operator, and have significantly diminished/eliminated the amount of defects on product being shipped.”

Rotoflex integrates several automatic vision systems into its equipment, which can automatically find defects in rolls and place them on the inspection table in front of the operator. This process ensures the removal of defective product prior to shipping to customers.

“Some of the new offerings we are currently working on include a new, programmable automatic knife system, eliminating manual setup,” adds Caparello. “With regard to roll finishing, we are nearing release of a new automatic turret rewinder that will increase productivity.”

ABG provides 100% print inspection with its fleyeVision camera system, allowing everything to work together with seamless integration in the Omega SRI. It checks for scratches, hickeys and letter or text irregularities, and can detect register shifts or color deviations.


DPR announces partnership with UV Ray
DPR has partnered with UV Ray to develop a UV varnish module for its Taurus TRS35PL label finishing system, a roll-to-roll system with digital laser cutting and laminating.

The Taurus TRS35PL converts pre-printed media into diecut labels at rapid speeds up to 30 m/m (dependent on laser power, cut pattern, and material being used). Unwinding, laminating, digital cutting, waste removal, rewinding, and length slitting in a single pass are all features of this label finishing machine.

A new feature of the Taurus TRS35PL is the integration of an inline UV varnish module as an alternative to cold lamination to offer improved label finishing in relation to the required application. It is equipped as a flexographic unit with an anilox cylinder capable of depositing 3.5 grams of varnish per square meter and a UV Ray lamp that cures it on the material. The power of the UV Ray lamp is automatically adjusted according to the laser cutting speed and when the media stops inside it, the protective shutter immediately intervenes.

“With our UV varnish module option, printers are no longer restricted to laminate labels with only cold foil, which involve other off-line steps, additional time, and equipment costs,” says Michael Panzeri, vice president of DPR. “Applying UV varnish to labels with the reliability and curing quality of the UV Ray lamp for a semi-gloss finish minimizes fading or discoloration of the label.”

“UV Ray is pleased to partner with DPR to provide their customers UV finishing options with their customized varnish module,” comments Stefano Maiano, UV Ray production director. “Adding an extra layer of protection with a glossy effect through UV coating results in a highly durable and visually appealing label.”