Upgrade logic for better control
Mar 05, 2009 at 11:43 pm by
Staff
If capital restraints don’t allow a new press, upgrades of control and systems technology can be a way of addressing productivity and safety needs.
On the prepress front, the introduction of CTP typically lifts colour quality even on older presses, thanks to the precision and predictability of the plates. Systems also make data available for ink presetting and press fingerprinting.
Presses designed for limited colour production – or even mono-only – can be brought to life with fresh thinking. Automatic colour registration systems deal surprisingly well with the problem of long colour-to-colour leads, and frequently reconfiguring a press to group units into colour towers can be a viable option. Both can extend the life of an older press, helping to deliver the mantra of ‘more and better’ colour demanded by advertisers and editorial departments.
Auto colour registration will typically also pay for itself through savings in newsprint waste, and systems can be moved to another press later if required ... a condition which was part of a recent QI Press Controls installation for Fairfax Media NZ’s ‘Waikata Times’ (see NewsLeaders in this issue).
And sometimes, the issue is simply that parts for an obsolete press drive are simply not available. “Replacing an old drive with modern units, not only solves this problem, but improves reliability,” says Stephen Kirk of Swiss specialist ABB. “In addition, older DC drives can be replaced with modern AC technology resulting in a reduction of maintenance costs.”
The company recently installed its Open Motion drive controller on the Goss and TKS presses at the 18 Dow Jones print sites in the USA, enabling conventional AC motors to be used in shaftless configurations instead of servo motors. “This not only reduces the cost of the motors but also makes a much wider range of motor ratings available, from 3kW to 3MW,” says Kirk.
Either bridges or satellite units – depending on the press configuration – can be fitted with position sensors and individual drives, converting a press to shaftless operation, and bringing benefits including more flexible operation, improved print quality and better web tension control.
Conversion to shaftless also widens options for press reconfiguration. Bridge and satellite units can be restacked freely to suit production needs, with units moved from one press to others at the same site, for example.
Shaftless technology also makes it easier to add towers from different manufacturers to a pressline. At ‘Norrköpings Tidningar’ in Sweden, units from three separate press manufacturers have been combined in a single pressline.
Upgrades and complete replacement of press controls open opportunities for integration with production management systems and plant-wide workflows. A number of players are active in this systems market including ABB, Harland Simon and manroland subsidiary ppi Media.
ABB’s MPS Production uses a ‘product structure librarian’ which ensures that only producible newspapers can be planned and problematic impositions can be avoided.
Harland Simon has a production advisory system which works out the relative difficulty of printing a specific colour product, using software, sales manager Charlie Brackley claims is unlike anything else on the market: “It’s based on an algorithm that calculates the best way to produce a particular product defined by the presses capabilities and the pressmen’s preferred printing methods, rather than a catalogue of predefined impositions,” he says.
The company’s Prima Colorware application provides information – either directly or via a third party layout system – on the availability of colour and job difficulty. Once a product is defined it is sent for imposition. This eliminates the need for a dialogue between pressroom and the advertising/editorial departments about colour availability.
At the ‘Dayton Daily News’ – which averages more than 90 separate pressruns a week – it has meant a move from manual production of layouts for each run, which had involved identifying reelstands and press units that will run, colour availability, and formers.
Automation put an end to juggling the binders full of hundreds of pressruns that which had been run over the years, all laid out by hand. Now a pagination department can run ‘what if’ scenarios as they plan the daily papers, leaving the press foremen to focus on quality and production.
Presetting and ink and water management functions in systems such as ABB’s MPS reduce makeready time, reduce startup waste and improve print quality. And because personnel requirements are also lowered, the payback period can be less than a year.