The Shaftless Shift
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At last year's NEXPO, shaftless-press technology, as presented by Swiss press-manufacturer WIFAG, was the new kid on the printing block. This year the kid had a lot of company, as three other manufacturers showed off shaftless printing options.
Goss Graphic Systems Inc., Westmont, Ill., unveiled its new Universal 70 shaftless press, rated at speeds up to 70,000 copies per hour. (A shaft-drive version is also available.) KBA-Motter Corp. of York, Pa., and MAN Roland Inc., Westmont, Ill., also offered shaftless versions of their presses at this year's NEXPO.
Of the five major U.S. press sales in 1997--one by KBA and two each by WIFAG and MAN--four were shaftless systems.
"I suspect that three or four years from now, no one will talk about anything but shaftless," said Jan Lindstrom, KBA vice president of technology. "So many mechanical parts get eliminated."
Shaftless technology replaces a central motor, plus transmission shafts, gearboxes and couplings, with individual, electronically controlled, synchronized motors at each printing-couple location. Each printing couple (or group of couples) is driven by its own asynchronous motor. The power of the motor is directly transmitted to the blanket cylinder via a timing belt, gear or direct shaft.
Because each impression runs individually, functions such as plate changing, pre-inking, pre-dampening, washing and start-up are totally independent. Each couple can be stopped, started and synchronized to suit the production requirements. All other driven parts also have individual drives, which are synchronized by a real-time control system.
The advantages of shaftless drives are many: less-complex gearing that results in lower investment costs; optimum register stability and reduced waste during press run-up and run-down; elimination of circumferential register units and clutches, resulting in faster operation; and reduced abrasion and less maintenance of AC servo motors because of their brushless drives.
An informal TechNews survey of the vendors places WIFAG, with 614 shaftless couples reported sold, at the top of the shaftless heap. Goss follows with a higher number, 740, but the company counts those under letters of intent. MAN has sold 200 shaftless couples, while KBA reports selling "in the hundreds."
Bern, Switzerland-based WIFAG demonstrated the industry's first shaftless newspaper web offset press in April 1996. Its first U.S. sale is also one of the industry's biggest. The World Publishing Company, Tulsa, Okla., ordered two WIFAG OF 370-GTD (gearless transmission drive) presses. The order includes 74 printing couples, two jaw folders and 14 auto-pasters. The first of the two presses will be delivered this fall, and is scheduled to be operational in 1998.
At Goss, Alan Sheng, vice president for technology, breaks down sales of shaftless couples into 400 single-width and 340 double-width units. The company is installing two of Europe's largest shaftless presses in Finland and Norway, the first of which should be operational by the end of the summer. Goss recently signed a letter of intent to provide a shaftless press to the Cedar Rapids (Iowa) Gazette.
The main feature of MAN Roland's shaftless system, which it refers to as direct drive, is that it drives the blanket cylinder by a motor without belts or gearing. According to MAN Executive Sales Manager Robert Wiedemann, that means the company's product provides even-more-accurate registration because of lower harmonic disturbance. It is also relatively maintenance-free.
MAN's latest sale was to The Des Moines Register for a double-width shaftless system, scheduled to go online in 2000. Another MAN system will be operational in Luxembourg by year's end, and another in the Netherlands in mid-1998.
KBA-Motter drives its shaftless couples with gears rather than belts, and employs what it claims are superior servos. KBA has installed nearly 1,500 servo motors, plus has another 1,500 on order for shaftless presses. It specializes in the use of off-the-shelf components for its systems, which means maintenance technicians can replace a motor in 20 minutes, said Lindstrom.
The company has had two recent sales of shaftless systems in the United States.
Rosalind C. Truitt, Presstime staff writer. E-mail,truir@naa.org; phone, (703) 902-1684; fax, (703) 902-1690.