Web-guide switch ups slitting accuracy for printed film
When two new slitter/rewinders failed to meet expectations, an Erhardt+Leimer upgrade stepped right in for Huhtamaki Flexibles.
By Contributing Editor Barb Axelson -- Converting Magazine, 9/1/2008 12:00:00 AM
What can you do when your new equipment doesn't live up to expectations? That was the dilemma John Edwards of Huhtamaki Flexibles faced early this year when two newly installed slitter/rewinders simply could not handle the complex printed structures manufactured by the Malvern, PA-based converter.
“My background is in maintenance electronics,” Edwards explains, “but my current title is process analyst, and that is essentially what I do, analyze problems and correct them. The problems can range from an inverter malfunction that prevents a line from running to the problem we were having with our slitter and rewinder pertaining to line and edge guiding.”
The E+L FE5002 digital color line/edge sensor, mounted on Huhtamaki Flexibles’ slitter/rewinder, features a robust mounting bracket and LED indicator scale with keypad.
The 160-person Huhtamaki Flexibles Malvern facility, part of Finland-based Huhtamaki Industries, focuses on multilayer, barrier-laminate technology for flexible packaging. The site, through blown-film making, adhesive- and extrusion-lamination and gravure-printing processes, manufactures every conceivable type of flex-pack material for products such as pouches and bags. “We use plastic, paper, and aluminum, and combinations of all these materials to deliver packaging that offers longer shelf life, puncture-resistance, aroma barriers, sterility, easy-opening and simple handling,” says Edwards.
“When our slitter/rewinder systems couldn't handle structures that were very reflective with narrow and sometimes intermittent lines for guiding, it prevented us from running certain jobs at top speed. Our most complex structures could not run at all. Our customers required a much higher standard than those systems could provide.”
Bad times, good times
Remarkably, it was taking up to three hours to set up and maintain the guide point, and the equipment could not run at its expected speeds of about 500 mpm on the slitter and 800 mpm on the rewinder.
The E+L color line/edge sensor uses red dots as a setup and run-time tool for the slitter operator.
“All of our other slitters also use E+L line and edge systems,” Edwards explains. “We did a trial run on one of these slitters with one or more complex structures, and we were able to run without any problems. This was an easy choice. We added E+L's WSS 5292 digital electronic-control system with motor actuator, including the FE5002 digital color line/edge sensor and an FX 5030 digital ultrasonic sensor for edge guiding with clear film, to retrofit to our existing slitter/rewinder machines.”
E+L tested samples, and the results were positive. Huhtamaki US installed the new control systems in May 2008. According to Joe Gvora, E+L technical sales, “[Our] technology provides accurate sensing of printed lines or contrasts on a wide range of paper, film and foil materials that Huhtamaki produces.”
A remote operator panel is installed on the back side of the slitter where the knives are. By pressing the up and down arrows on this panel, the operator can align the printed image with the slitter knives. “This immediate feedback for alignment of the printed material to the slitter knives reduces waste,” Gvora explains.
All of the other system components (sensor, controller, actuator, main operator panel) are on the front side of the slitter, where the unwind roll is located. Without the remote control panel, the operator would have to walk around the slitter to adjust the guide point, then walk back to see if the adjustment is accurate. If not, they must repeat the process. “These adjustments are made while the slitter is running,” Gvora says. “That's why the remote panel saves operators time and cuts waste.”
Good-to-go faster
After less than eight hours of actual downtime to install the new system and train operators, everything was set to go.
Production speeds have increased with the E+L guiding upgrade to an average slitter speed of 500 mpm; the rewinder now runs at about 500-800 mpm, depending on the job. “New printed structures that would not run on the original slitter or the rewinder now run without any problems,” Edwards notes. “In addition, on special jobs with print next to the line, we can run in line-guide mode using printed images instead of the line.”
And another one of his operators told Edwards, “Huhtamaki has spent millions of dollars on new equipment, and it's all great equipment, but as far as I'm concerned, this investment is by far the best.”
| More Info: | ||
| CONVERTER: | ||
| HUHTAMAKI FLEXIBLES, INC., 484/527-2042, fax: 484/527-2100, www.us.huhtamaki.com | ||
| SUPPLIER: | ||
| ERHARDT + LEIMER, INC., 864/486-3000, fax: 864/486-3011, www.erhardt-leimer-us.com | ||
The payoff, according to Edwards, is that setup time has dropped dramatically. “The new machine took off like a champ. As one operator told me, 'I just set up a job in 15 seconds. That same job used to take me three hours to set up.'”Looking for a solution, Edwards contacted his web-handling control system supplier Erhardt + Leimer (www.erhardt-leimer-us.com). E+L also provides sensors, cameras and vision technology for guiding and inspection applications.
