- November 01, 2000, Teresa Koltzenburg, Senior Editor
Is your operation's roll cleaning system like the "dishwasher" my family used to have when I was a kid? When asked if we had one, my mother would reply comically: "We have three of them—Teresa, Chris, and Cliff [myself and my brothers]." Unlike my family, your operation probably has taken advantage of technological innovation and incorporated automatic cleaning equipment. If not, then it certainly is something to think about; current roll cleaning systems are reported to provide thorough, reliable cleaning and to decrease the risk of operator injury.
Ron Egan, president/owner of R.G. Egan Equipment Inc., Webster, NY, notes that past cleaning methods have put both operators and production levels at risk. "In the old days, a common way for operators to handle roll cleaning was for them to tape a rag to a stick, reach inside the machine, and try and clean the debris. Sometimes they were successful, and sometimes the stick got caught and caused a machine shutdown."
But, says Egan, converters today are steering away from manual methods and are taking the more sophisticated PLC route. "Converters want an on-line cleaning device that's very compact, so they don't have to relocate a lot of other components in the machine. And, of course, they want versatility. They want to be able to use a cleaning liquid if they need it. Or, if the process calls for dry conditions, they want to be able to clean it by using a dry cloth. They want to be able to clean a particular location on the roll, and they want to be able to vary the intervals. All of that can be done inside the PLCs very conveniently."
Today's process roll cleaning systems are capable of cleaning many types of rolls—calendering, laminating, printing, coating, even chill rolls—and they provide thorough cleaning while the machine is in production. Yet the precision of "on-line" roll cleaning is being pushed even further by roll cleaning innovation. According to Gary Larsen, president, Polymag Tek Inc., Livonia Ctr., NY, his company has patented a way to clean rolls more aggressively that requires even less operator intervention. "We've found that our traversing cleaners [which are used mostly in contact cleaning roll applications] are not perfect. For instance, they clean 99.5 percent of the dirt on the roll each cleaning cycle. But, over time, you get this accumulation of that last half percent. After several weeks or months, you would have to hand-clean the roll. But we've come up with a high-pressure wash technique, and we've found that it actually increases the cleaning efficiency up 100 percent, so no hand cleaning is required."
Anilox rolls provide an especially tough cleaning task for converters. Ink gets trapped inside the small roll cells and, if not cleaned properly, the ink can contaminate—even ruin—subsequent printing jobs. Off-line cleaning provides a very thorough washing method of these difficult-to-clean rolls, says Bob Temple, president and owner of Absolutely Micro-Clean, Rancho Cordova, CA. "Our off-line cleaning method utilizes an enclosed chamber and a proprietary plastic. That plastic is soft and malleable, so it tends to fold over, and it's applied to the roll mechanically by compressed air. So, we're actually blasting the debris off with 60 pounds of pressure. It literally grabs the ink and pulls it away. This process can be confusing for some to conceive; they envision something that actually has to go into the cell as a physical particulate. That's not true. The cleaning medium [the plastic] just has to get an edge into it and scoop out the material, and it's able to do that quite well."
Like dishwashers, roll cleaning systems aren't what they used to be: They are much better. They clean thoroughly, reliably, and they can help you maximize your production time. If only I could convince my mother that the same is true for dishwashers... then I could spend the holidays maximizing my food-recovery time instead of standing by the suds, performing my manual and much-dreaded dishwasher duties.