Maximize Your Anilox Investment

With anilox rolls being a main artery of the flexographic printing process, you would be foolish not to maximize their value. Not to sound trite, but the United States economy is hurting at the moment, and it’s not easy getting the most bang for your buck these days. Consider this: statistics show that 80 to 85 percent of all rolls are damaged prior to being worn out, according to Mike Huey, technical graphics manager at Western Division, Harper GraphicSolutions (www.harperimage.com). “Routine cleaning, inspection, and storage all play a large factor in providing optimum care for these delicate instruments,” he says. “Identifying root causes of damage and enacting measures to protect against future damage is critical to prolonged anilox life.” There are also other ways to get the most out of your anilox rolls, including resurfacing existing rolls and working with your suppliers to enter into buying programs.

Handle with care

Considering Huey’s comments, a good way to start getting the most out of your anilox rolls or sleeves is to take care of them. “Better housekeeping, care, and handling of your sleeves and anilox rolls is the key to getting the most bang for your buck,” says Ashley Foran, marketing director, ARC International (www.arcinternational.com). “It all sounds so simple, but in truth, very few printers take the time to allow for cleaning of their anilox rolls and sleeves.”

There are a number of things printers can do to optimize the lives of ceramic anilox rolls, according to Mark Hahn, vice president of sales and marketing, AAA Press International, Inc. (www.aaapress.com). These include proper setting of steel doctor blades to shear ink from the face of the roll; use of ink magnets or filters to remove larger metal particles present in some fluorescent and standard ink colors; proper use of ultrasonic anilox cleaning systems; proper use of ultrasonic anilox cleaner (using the 90-10, no more than 5 rule); regularly cleaning the cleaning solution when it dips below the recommended pH; and experimenting with press side cleaning pastes, which remove 95 percent of impacted and dried ink without the use of abrasive cleaning methods.

Huey concurs. “Inspection equipment and a good maintenance program of cleaning rolls and deep cleaning rolls help printers best maintain their anilox rolls/sleeves to ensure long life,” he says.

Carol Harrison, general manager, CTS Industries (www.ctsindustries.com), concurs that keeping the anilox rollers clean is a critical part to extending the life of the anilox roller and should be included in a routine maintenance plan for the press. “Storage covers should be utilized to protect the rollers from damage and the environment,” she states. “It also helps protect the roller when moving from one station to the next.”

Huey continues, “Use magnets/filters and best practices to protect against scoring and end damage. Communicate any concerns you are having with your suppliers as they may have ideas [you can do] on your end as well as alternate methods of manufacturing on the supplier’s end.”

Failure to protect the relatively fragile coating on both sleeves and rolls will lead to coatings being fractured at a minimum and, more severely, will result in complete bond failure with areas of the coating completely separating from the face of the core, says Foran. “Sleeves are very prone to this if they are dropped or improperly handled when taking them off the air mandrel,” she adds.

Buying in bulk equals savings

Costco, B.J.’s, Sam’s Club—these membership warehouses allow consumers to make bulk purchases to save money. Printers can do the same thing, according to Harrison. “Find an opportunity to look at quantities of two or more,” she says. “Discounts are readily available to the printer.”

Hahn adds that printers can get the biggest bang for their buck by entering into annual corporate blanket programs with their anilox suppliers. “By committing to an annual purchase program, most printers can save between 5 and 10 percent simply by agreeing to purchase 75 percent of the volume of rolls they bought the previous year,” he says. “Buying this way allows the supplier to keep stock of the anilox roll bases coated with ceramic, leaving only the engraving specification to be submitted by the printer resulting in quicker delivery in a pinch.”

Reuse, reuse, reuse

Much like you can resurface the brake rotors for the disc brakes on your vehicle before having to replace them, you can resurface your anilox rolls. Sleeves are more difficult to resurface and whether or not they can be relies on how they were handled.

“Most every roll can be resurfaced multiple times provided it was correctly engineered in the first instance,” says Foran. This means, she continues, using the correct quality of steel, having the correct wall thickness, ensuring the journals and headers have been adequately set into the core, and that the roll was dynamically balanced to suit the speeds a printer intends to run. “Failure to carry out any of these factors will or can result in the roll not being able to be reconditioned without incurring additional major costs other than simply recoating and engraving the surface of the roll.”

Sleeves are a different story. “[They] are extremely difficult to rework and, depending on how they have been handled and how long they have been run, often fail the incoming inspection process due to extreme mechanical breakdown between the various interlayers and the external core,” adds Foran. At the very least, she contends that this can mean unacceptable total indicated runout (TIR) or, in many cases, fracturing of the end ring and delamination of the internal sleeve.

Hahn asserts that resurfacing anilox rolls 13˝ and larger can be cost-effective, however, “the converter must take into account freight costs to and from the supplier and obtain a proposal for removing, resurfacing, and engraving the roll, along with potential costs to repair journal damage from constant use.”

David Skellie, president, Interflex Laser Engravers (www.laserengrave.com), contends that resurfacing anilox rolls and sleeves is possible and a cost-effective solution. “This is based on proper care and managing of these rolls/sleeves to prevent extensive damage or reduction of diameter due to corrosion or continual rework turndown,” he explains

Keep the condition of the base in mind. If it is in excellent condition (no spun journals from bearing wear, bent shaft, extensive rust, etc.), then, according to Harrison, send the old anilox for re-engraving. “All of the material is stripped down to bare metal and rebuilt with a guarantee,” she says. “This can save hundreds of dollars per roller, depending on press design.”

Just what the doctor ordered

Doctor blades are a small, but pivotal, part of ensuring your anilox stands the test of time. Harrison says that “Changing the doctor blade more often is also critical to the life of the anilox roller,” citing that the cost of a blade is less than half a percent of the cost of an anilox roll.

“On press, the use of the correct blade, having good alignment of the blade, and not over-pressurizing the blade to the face of the anilox are all factors that will either extend or reduce the life of the anilox and its overall performance,” says Foran.

Technological advances

According to Harrison, new technologies have allowed anilox rollers to have a better cleanup and ink release, which is critical in the life expectancy of the anilox roller.

It all comes back to how you take care of your aniloxes, however. “Modern laser systems and coating technologies have enabled higher line counts and volumes to be offered for all markets and ink systems,” says Foran. But printers must invest. “Without the right ink and coating formulations and adequate training of your operators, you will not be able to achieve the performance and longevity that they are capable of.”

Ultimately, the anilox rolls remain a vital part of the flexographic process. “Anilox rolls are precise tools,” says Huey. “They are considered the heartbeats of the press. Consistency and repeatability of anilox rolls have a direct correlation between uptime and profitability when manufactured to within specifications.” He cautions that some printers may consider an anilox roll a commodity, but in reality it is a precise liquid-delivering instrument. “Anilox rolls are a necessity,” he says, “and targeting the right rolls, surface, geometry, and volume will aid in a customer’s success or failure.” pP