Perfectors Illustrated

Press manufacturers are emphasizing the productivity of sheetfed perfecting at drupa 2008. Most are unveiling enhanced and, in some cases, re-engineered machines that meet the inherent challenge of turning over sheets with fresh ink on both sides at significantly increased speeds. Cylinder sizes and transfer configurations, ink-repellant surface coatings and revised gripper arrangements are among the improvements. On many presses, venturi air systems, video sheet monitoring, targeted powder sprayers and control systems have all been revised to provide ever higher perfecting speeds and mark-free printing. Ever more automated conversion between straight and perfecting modes simplifies changeovers for models so equipped. Larger image areas and the ability to handle a wider range of stock weights and thicknesses are among improvements.

Akiyama is making the European debut of its Mega Jprint stacked press, first shown at IGAS in Tokyo last fall. Pulling the sheet continuously through alternating upper and lower units, it only requires a lead-edge gripper area. The newest versions of the 15,000-sph Mega Jprint 440 and 14,000-sph Mega Jprint 540 in 28.31×40.56´´ formats include multiple updates: new sucker heads; a swing gripper base made of new materials with a new mechanism to prevent sheet overruns; a delivery with two additional transfer cylinders to suppress paper movement; and an endless paper-guiding tape for rub-free movement of the sheet from final cylinder to delivery belt. Also new is the control for the paper release cams that supports various types of papers without requiring adjustment of the delivery fan or slowdown wheel for each job.

Heidelberg is launching the 18,000-sph Speedmaster 29×41´´ XL 105 perfector at drupa 2008, with a new maximum perfecting speed of 15,000 sph and the capability to perfect up to 24-pt. stock at that higher rate. The XL 105 uses the same perfecting system as the new Speedmaster XL 75 (which, in turn, is based on the Speedmaster CD 74 that it succeeds). The approach employs Heidelberg’s three drum, 2-2-1 configuration—a double-diameter transfer cylinder, double-diameter storage cylinder and then a single-diameter eccentric perfecting drum. The eccentric perfecting drum expands to full size to lend stability to thinner sheets, or folds up to allow more room for thicker sheets to move through the press without marking. The 29´´ Speedmaster XL 75 is available with different cylinder sizes, either the C format (20.87×29.53´´) or the larger F-format (23.82×29.53´´). In development are perfecting versions of the new large format Speedmaster—the 52´´ XL 145 and the 64´´ XL 162—which it is anticipated will use the same drum geometry as the XL 75 and XL 105.

Enhancements to the perfector incorporated into the XL 105 include a new Dynamic Sheet Distance Control, a new storage drum with built-in vacuum system and a new venturi system.

The Dynamic Sheet Distance Control monitors the sheet and regulates its distance between the guide pans and cylinders as it is turned over. A new channel suction system built into the ribs of the storage drum stabilizes the sheet better at the press’s higher perfecting speeds and improves front-to-back register as the sheet is put into the perfector. They apply uniform suction to the sheet over its entire length, even with thick printing stock, so that the sheet is held securely on the storage drum right from its front edge—a key factor for the high register accuracy, says Heidelberg. Changeover from straight to perfecting is done automatically. All air and suction configurations are also preset automatically according to sheet size and thickness as entered into the Prinect CP2000 Center console. Once the sheet is perfected, an enhanced venturi guide plate with a new center Air Jet keeps heavier stock from touching bottom and lighter stock close to the next cylinder.

Sheets moving off the last impression cylinder and toward the delivery on the 2008 XL 105 and 40´´ long perfectors travel via new, variable double-diameter transfer jackets on cylinders after the perfector and are controlled by new upper suction disks. They are then slowed by the Dynamic Sheet Brakes as they drop into the delivery pile.

KBA At drupa 2008 KBA is announcing a new Rapida 106 and a re-engineered Rapida 75 with perfecting options, and is demonstrating big 4/4 perfectors including an enhanced Rapida 162a and a high-performance package for the Rapida 142 long perfector. The 18,000-sph (straight) Rapida 106 in 29.5×41 75´´ format evolved from the Rapida 105. The new 15,000-sph (straight) Rapida 75 offers a larger sheet size—20.5×29.5´´—and is also available in a special 23.5×29.5´´size for label and packaging printers. A perfector version of the 47.25×63.75´´ Rapida 162a with a bigger sheet size is being shown. Previously, the printable width during perfecting was 43´´ on a reduced sheet width of 44´´; this has now been increased 3´´ to 46.´´ As a result, the maximum sheet size of 47¼×63¾´´ can be run through the press in perfecting mode.

The a new high-performance package for long perfector versions of the 40×56´´ Rapida 142 includes sheet guides and suction stations that are controlled remotely from the console.

The core component of the large-format Rapidas for 4/4 work is KBA’s convertible single drum perfecting unit. Conversion between straight printing and perfecting is automatic, takes about 60 seconds and is controlled from the ErgoTronic console. Changes in blower settings at the perfecting unit or delivery are monitored at the console by video cameras in the press, and the settings adjusted if necessary. All job-specific settings for perfecting and air-blown sheet guidance can be stored at the console for repeat orders.

KBA boasts a gripper system designed to accommodate changes in substrate thickness from minimum to maximum with no need for adjustment. The firm notes a wide range of substrates its presses can perfect, from light weight stock up to 28-pt. board.

According to KBA, its specially treated chromium impression cylinders require no special jackets—providing a significant savings in expense for replacement jackets. Ceramic-treated shells have replaced Super Blue material above the skeleton cylinders that transfer the sheet after perfecting. A paper saving of about one sheet for every 110 printed results from reducing the print-free corridors (used for sheet guidance) on the sheet to five.

The 56´´ press at drupa features a new air guide system that levitates the substrates up to the slowdown wheels. The slowdowns have been designed so that there is no need to minimize press speeds to handle lightweight stocks with heavy coverage coming into the delivery.

Also being demonstrated at drupa is the new Qualitronic Professional, which automatically maintains color and density on both sides of the sheet, and an improved powder sprayer with HEP nozzles that reduces powder consumption in 4/4 production.

Komori perfectors debuting or showing at drupa include the small format Spica 529P, the 40´´ Lithrone S40P convertible perfector and the 44´´ Lithrone S440SP and 40´´ Lithrone S40SP dedicated double-decker perfectors.

Komori is showing the 5-color version of the 20.67×29.25´´ Spica 29P perfector for the first time at a world show. The Spica is designed for tight turnaround times and short to medium runs of a variety of jobs. Automation includes fully automatic 60-second changeover between straight printing and perfecting.

The 4/4 Lithrone S440SP at drupa features the launch of the new Komori PQA-S Print Quality Assessment System, available on all Lithrone S40 presses. PQA-S inspects the sheet inline, creates a digital memory of it, and then compares subsequent sheets with the memorized data, identifying any incorrect sheets for the printer.

The Lithrone S40P 8-color perfector, with triple-cylinder, all-double-diameter perfecting mechanism, is being shown demonstrating Komori’s new Videoscope for real-time simultaneous monitoring of the four most critical air zones through which the sheet passes. It provides slow-motion playback, memory and on-the-run touch screen adjustment.

New this year are enhancements to the KHS-AI software that include self- learning properties to adjust ink, air and register settings as presses break in over time, and allow storage of automation steps for different jobs and daily start-up.

Both the Lithrone S440SP and S40P at drupa feature Komori’s new air pre-set system, the operation of which is integrated into the new PQC-S touch-screen monitor. Pre-setting can be made from the console for all feeder and delivery air systems, the printing unit transfer cylinder air guides, and—on S40 long perfectors—all the air controls throughout the three-cylinder perfecting transfer system.

manroland’s perfecting versions of the 64´´ plus and 73´´ Roland 900 XXL are being launched at drupa. These large perfectors use a new three-cylinder perfecting system in place of the single-drum system on smaller format presses. The three-drum system—all double-diameter cylinders—is seen as providing better performance for turning the large sheets. Perfecting options are also available on the 23×29´´ Roland 500, the Roland 700 Hi-Print in 28.2× 40.2´´ and 30.3×40.55´´ and the Roland 700 Direct Drive in 28 x 40.2´´.

Both the Roland 700 and 500 series include fully automated, push-button straight-to-perfecting mode changeover in less than a minute from the console. Maximum speeds on the 700 press series are up to 17,000 sph in straight mode and 13,000 sph in perfecting mode. Roland 500 presses are available in straight and perfecting modes at 15,000 sph or an 18,000-sph model that perfects at 16,000 sph.

Both Roland 500 and 700 perfectors feature a single double-diameter sheet-turning drum followed by double-diameter cylinders after the sheet is turned and touchless transfer for print quality. The single, large-circumference drum is seen as the best choice for providing gentle travel on standard-size sheets, as well as in reducing the number of sheet transfer points.

Downstream from the perfecting cylinder manroland offers impression cylinder surfaces with optional OptiPrint advanced replaceable cylinder jackets for very demanding applications.

Also available is the InlineObserver multi-camera monitoring system. Images are shown on a separate display screen and any adjustments can be made without stopping the press.

A Venturi Air Track system throughout the press uses a series of venturi nozzles to maintain ripple-free sheets.

manroland’s AirGlide Delivery includes a new suction roller with improved braking effect that slows and rests sheets in the delivery pile. Also new on Roland perfectors is a cardboard option that provides a series of ribbed air tracks after the perfecting device for the perfecting of up to 24-pt. board.

Mitsubishi Lithographic Presses’ new perfectors shown at drupa include a V3000TP dedicated tandem perfector and a V3000R convertible perfector. The new presses include fully automatic Simulchanger, one minute plate changers, speeds up to 16,200 sph in both straight or perfecting, upgraded software and remodeled exteriors.

The 41×29´´ V3000TP tandem perfector is available in up to 12 printing units. On its tandem perfectors, MLP splits its upper and lower printing units rather than stacking them to maintain standard cylinder configuration and help run thicker substrates. In the V3000TP, the first units are regular print units, but inverted, so the sheet is brought in higher and printing is done directly on the bottom side first. The sheet then goes through a three-cylinder translink unit with double-diameter transfer cylinders to bring the sheet down to the next level, where conventionally arranged units print on the top of the sheet.

Because the sheet never turns over, only a single lead gripper edge is required.

The 41×29´´ V3000R convertible perfector features a new style three-cylinder reversing unit with all double-size reversing cylinders that accommodates up to 24-pt. board, for a wider stock range at the faster 16,200-sph speed. Also new is a single-gripper shaft mechanism for both reversing and straight production that provides easier changeovers and better sheet transfer.

On the V3000R 4/4, the sheet travels through four units then comes into the first transfer cylinder in the perfector. The tail of the sheet is flattened on suction pads and the current lead edge goes under the cylinder. The reversing cylinder then grabs the tail edge of the sheet from the suction pads and pulls that end through, so it becomes the new lead edge and, in that motion, the sheet is flipped over. The sheet then goes through another four units.

The V series presses have a totally redesigned shorter delivery with more cylinders and a belt type sheet guide running at the same speed as the sheet. The new system accommodates faster speeds and thicker substrates.

Sakurai’s 15,000 sph Oliver SDP series convertible perfector presses—the 31.125×23.625´´ Oliver 75SDw/SDPw and the 26×20´´ Oliver 66SD/SDP and Oliver 466SDP—use computer controls to automate perfector changeover. This is accomplished in less than two minutes by “one-button activation” at the console.

In perfecting mode, the sheet bypasses the normal transfer point and is held firmly and smoothly against the transfer cylinder (storage drum), while remaining in the transfer cylinder grippers. When the tail of the sheet is at the transfer point of the perfecting cylinder, vacuum pads straighten and smooth the sheet so that the perfecting cylinder grippers can accurately grip the tail. As the perfecting cylinder grippers securely grip the sheet, the transfer cylinder grippers release it—allowing the change of control to the tail. Register of the sheet (front-to-back) is maintained because the sheet is not being re-registered to the tail, Sakurai explains. All register is accomplished initially at the lead edge and maintained throughout the perfecting operation.

Shinohara 52, 66, 75 and 79 series convertible perfectors, which range in size from 14×20´´ to 23×30´´ formats, switch between straight and perfecting in about a minute, says a company spokesperson. The semi-automated changeover system uses a safety monitor to guide operators through three steps. Shinohara’s rigid, mono-cast turnover cylinder uses a patented master/subgripper system said to offer precision, speed and high reliability in single- or double-sided printing. During one-sided printing, only the master gripper seizes the sheet. During two-sided printing, both master and subgrippers are active.

The perfector includes a paper end-guide system to control the tail edge of the sheet that has already been printed, so it is properly guided to the next grippers. It is positioned around the double-diameter perfecting cylinder, so that it can wrap the sheet around the cylinder efficiently while still applying tension to the sheet and feeding the sheet reliably into the gripper.

xpedx Ryobi has upgraded its six-up 23×31´´ 784 press series to use the same convertible perfector configuration as that used on the 23×29´´ 750 and 14×20´´ 520 series presses. The convertible perfectors are fully automatic, requiring only that paper size be entered at the console for push-button changeover from straight to perfecting. The perfector now incorporated into all three series models uses a specially coated, double-diameter cylinder on the first transfer, followed by a triple diameter cylinder (the storage drum of the perfecting unit) that holds the paper as it is turned back around, so the double-diameter turning drum can grab the tail of the sheet and carry it to the remaining units.

Ryobi notes that there are only four gripper changes on this system and no tight turns for the sheets.

It also reports that long perfector customers are ordering UV curing systems as a matter of course to dry the sheets as they go over the storage drum as an additional safeguard against marking. Today’s glossier-finish UV inks are seen as greatly facilitating the acceptance of UV drying, especially on heavy coverage areas.

Ryobi’s new 41´´ 1050 press, being shown at drupa for introduction next year, is also said to have a perfector version under consideration.