The blending of state-of-the-art software and servo technologies is now being applied to both narrow and mid web flexographic printing press platforms by leading press manufacturers.
Gone are the days of relying on mechanical finesse and a good eye for color to produce the perfect label—time and again.
All photos courtesy of Nilpeter USA
The mechanical, manually controlled presses of yesteryear have served our industry well. It is time to embrace the technological boom and employ the automated press technologies offered today. Gear bumping and chatter are truly a thing of the past. A poignant comparison would be to ask yourself, is my next automobile purchase going to be an electric vehicle or one with conventional, fuel-based technology?
Set, Store, Print
Software driving today’s “smart press” is a combination of innovative packages including several components.
An automation package for each print station and diecutting cassette incorporates job save functions that enable the ability to save all parameters of a job, recalling them instantaneously for exact repeatability:
- Anilox pressure adjustment
- Plate sleeve pressure adjustment
- Automatic setting of web tension
- Automatic setting of corona treatment
Pre-setting (by repeat size) allows all plates to be rotated into perfect registration when the sleeves are loaded into the print station. A job-detailed library enables storage of parameters by job or substrate, and listing of all settings.
An advanced registration package for each printing and diecutting unit consists of:
- Advanced “Twin Eye” mark reader P2C (print-to-cylinder)
- Automatic length register system
- Pre-register by printed mark (self-finding automatic register)
- Enhanced reading capacity for glossy material
- Automatic teach function for setting of all units
- No-mark register function
There are also progressive print impression adjustment features for all printing units, providing linear increase in pressure and speed, while ensuring color consistency.
Color management and automated inline print inspection for inline scanning, quality inspection and comprehensive inline spectral-based color measurement consists of:
- Web viewing, inline
- Bar code grading
- Light tower
- Spectrophotometer-based color measurement for controlling brand/spot colors/color bars
- Motorized traverse arm for accessing the entire width of the web
- Programmable, precise sequencing for automating in-image measurement
- Touchscreen monitors with inline live data display
The workhorse behind the software is the precision of today’s servo technology incorporated by most, if not all, leading press manufacturers. Servo drives allow the exact repositioning of all the parameters addressed here. The key to successful integration of the servo motor is the ergonomics of their placement. You will find presses with one to eight servo drives per print station and implementation in unwind, rewind, waste removal, etc.
The key in evaluating the servo/software technology is to thoroughly understand the manufacturer’s use and integration. As a rule of thumb, the more servos and software packages, the higher the level of automation that can be achieved.
Pit Stop
When a truly smart press is utilized to its full potential and a “pit stop” changeover environment is adopted, it allows the operator’s function to be redefined. The operator no longer should be viewed as a jack of all trades. The operator’s role should be one of understanding the principles of flexographic printing, and all operators must be trained in how the functions of today’s “smart press” achieve the desired results.
FTA’s FIRST (Flexographic Image Reproduction Specifications & Tolerances) Individual Certifications are the perfect solution for training in the principles of flexographic printing. FIRST supports the methodical approach to process control, optimization, fingerprinting, characterization and process improvement as outlined in CGATS TR 012-2003 (Graphic Technology – Color Reproduction and Process Control for Packaging Printing).
While each organization may use its own workflow, based upon its specific needs, there are certain fundamentals that are universal to the flexographic printing process.
With a firm understanding and application of the FIRST methodology, flexographers can identify potentially troublesome issues, benchmark press performance, utilize statistical analysis to maintain optimal conditions, perform accurate device calibrations, identify improvement opportunities and preserve stable conditions for repeatable results—all with the end result of satisfactorily reproducing the graphic design.
Once operators are trained at a Level I and Level II of FIRST Press Operator Certification, they are qualified to run today’s smart presses. The press training provided by the smart press manufacturer of your choice then becomes the cornerstone for applying the principles learned to the results achieved by successful training on the operations of the press.
With the training achieved, a pit stop approach to changeovers and setups is the natural progression. Ensuring all necessary items are press side, when the press is changed over or initially set up, is key to its success. Through proper kitting of the job and precise plate mounting employed, today’s smart presses can be fully changed over in three to four minutes per station—this includes sleeve, anilox and ink change. The new job will run up to color and come into registration within the length of the press.
The next step in maximizing a pit stop approach is embracing today’s capabilities of printing with an expanded gamut (EG) ink configuration. When fully employed with an 8-color EG ink setup and the proper prepress software, a minimum of 90 percent of the Pantone Color Matching System can be captured. The benefits of this platform in managing ink inventory and eliminating ink changes are monumental.
The quality and throughput achieved through the implementation of this technology, training and pit stop approach far exceed the cost of this investment. The reality is those that embrace this shift in our industry will continue to work on future ROIs. And those that don’t? Simply put, you must Evolve or Die.
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