The global printing leader now saves $50,000 per press, per year, with new controllers, WinCC SCADA software and the TIA Portal.
There’s one constant in the books, catalogs, direct mail, directories, journals, packaging, publications, and retail inserts published by Quad/Graphics. Output color and quality must always be flawless with minimal waste.
As a leader in its field, Quad/Graphics has many printing plants around the world. They all have capital-intensive integrated printing presses that feature complex, end-stage material handling capabilities like portable, interchangeable conveyors, trimmers, folders and stackers. The Quad/Graphics M-3000 web press, for example, stands almost 30 feet tall and stretches 175 feet in length. It can automatically splice a fast-spinning, near-depleted paper roll with a fresh but much slower-spinning one weighing a quarter-ton or more without slowing down. Paper speeds through the press can run 50 feet per second, resulting in an output of tens of thousands of collated units each minute.
Designing the equipment to meet these demanding requirements falls to QuadTech, a Quad/Graphics group that develops and supports advanced, technology-based systems. That group recently upgraded its systems, making changes that could save the company $50,000 per press per year.
The basis of these systems is the QuadTech Product Tracking System (PTS). Its primary function is to track waste events in the printing process and discard faulty products. It also provides count data for all printing products that are in-process.
The PTS monitors signals related to waste events from the roll splicer, in-line print units, inspection systems, and other points along the length of the press. Examples of such events are roll splices, blanket press washes, and cleaning of printing plates. These steps inevitably result in bad product as print quality is compromised. As equipment ramps up and print quality resumes, bad products need to be tracked and discarded.
Encoders are used to track the position of each waste event. The PTS also interfaces with the conveying and stacking equipment to provide speed-following signals, control the waste gates, and send count information to operators and higher-level systems. QuadTech started using the Siemens SIMATIC S7-300 series PLCs in the PTS in 2000 for automation, monitoring and control.
A few years ago, the company adopted the Siemens SIMATIC WinCC SCADA platform for the HMI, migrating from a Wonderware based system. This helped simplify programming, code management and support, while eliminating Wonderware’s licensing costs.
Quad/Graphics’s technical challenges exploded in 2010 when it embarked on an aggressive global acquisition strategy. Today the company has six times the number of facilities as before, including a retail insert business that produces high-volume color flyers for major retailers. This introduced a new set of variability challenges, including complex deliveries with portable, interchangeable conveyors, trimmers, folders, and stackers.
QuadTech’s staff also had to upgrade many different kinds of legacy printing systems by installing PTS technology and then supporting their operation. They also had to teach operators and technicians and troubleshoot the PTS.
In response to all these changes, QuadTech decided to rethink and reengineer the PTS for these more demanding capabilities. Its timetable coincided with the debut of the Siemens SIMATIC S7-1500 PLC family, which included the S7-1200 basic controller and ET-200SP distributed controller.
QuadTech’s strategy for this reengineering centered around six goals.
The first is adaptability. While the S7-300 series in the PTS is quite versatile, each press type required its own unique operating software code. For example, changes made for the retail insert application required a significant deviation from the base code, which made it difficult to install and troubleshoot. QuadTech wanted a single, modular code set that could handle every type of press and printing need.
Developers also sought to reduce the amount of Statement List (STL) code, which resembles arcane assembly language. STL is generally by plant electricians, service technicians and others, so the goal was to convert PTS code to ladder logic.
Future-proofing was third on the list. The S7-300 PLC offered many years of useful life, but the team turned to its successor, the S7-1500.
New designs also had to offer scalability. The S7-1500 PLC series met this need, especially with the drag-and-drop programming capabilities of the TIA Portal engineering framework.
Quad/Graphics’ expansion made ease of support another critical factor. Personnel in many locations were unfamiliar with the QuadTech PTS. So the PTS had to become easier to install, use and troubleshoot, trimming the technical support load upon the company’s limited resources.
The sixth factor was a given: reducing total cost of ownership. Code simplification alone delivered big savings in time. Costs were also trimmed by using the TIA Portal’s common engineering framework, which simplifies operations throughout the life cycle.
All these goals were achieved by implementing Siemens technology.
The savings in development time provided by the TIA Portal are a cornerstone of the business case for migrating to the Siemens platform. It helped pay for the new hardware, which has provided advanced features, integrated diagnostics and modular scalability. These advantages will continue providing dividends in the years to come, along with easier installations and updates. Additionally, technical support calls have been reduced and most of those calls are from operators or maintenance technicians who are learning the new system.
A big part of the cost-justification is better waste management, which saves about $50,000 per press each year. This results from more precise counting, which minimizes over- and under-runs when a waste event occurs.
Now, after creating a single code-set that’s adaptable to every installation, changes using the TIA Portal are quick and easy. Another measure of success is that in-plant operators, field technicians and other stakeholders have given extremely favorable feedback.Have an Inquiry for Siemens about this article? Click Here >>