Mitsubishi Heavy Industries Technical Review Vol. 46 No. 1 (Mar. 2009)45

New Sheet-Fed Offset Press Series: DIAMOND V3000

SHINICHI FUJIMOTOYASUHIKO HIRATAYOSHIRO MATSUURA

HAJIME YAGIYASUHIRO MOCHIZUKIHITOSHI HIROSE|1. Introduction
The development of the high-speed sheet-fed offset press has seen many challenges.
Mitsubishi Heavy Industries, Ltd. (MHI) has succeeded in achieving speeds as high as 13,000
sheets per hour (sph) with the MITSUBISHI 3F and 16,000 sph with the DIAMOND 3000.
However an increase in speed does not always result in an improvement in productivity undermultimix low-volume production conditions. The DIAMOND V3000 was developed for these
conditions to achieve a substantial improvement in productivity.

|2. Concept of the DIAMOND V3000 series
The design goal of the DIAMOND V3000 series was to achieve a substantial improvementin productivity. Under multimix low-volume production conditions that have been the subject ofrecent attention, the press downtime is relatively long, resulting in a low operation rate (Figure 1).
The causes of press downtime can be categorized into the following five categories:
preparation, adjustment, cleaning, maintenance, and miscellaneous. The DIAMOND V3000 series
is designed to reduce downtime because it is designed for oil-less production as well as simplified
lubrication, cleaning, inspection, and maintenance.

Figure 1 Daily activity breakdown|3. Productivity improvements
Figure 2 shows the major productivity improvements.

Figure 2 Major productivity improvement items(1)

Oil-less bearing and torsion bar for the gripper shafts
The sheet-fed offset press uses grippers to transfer the sheets from one cylinder(impression cylinder or transfer cylinder) to another. The oil-less gripper shaft bearing andMitsubishi Heavy Industries Technical Review Vol. 46 No. 1 (Mar. 2009)46

torsion bar are used in the gripper area to eliminate the requirement for greasing. This saves
many man-hours for each grease application (120 lubrication points every two weeks) whileeliminating the problem of excess grease scattering on the sheets.

(2)

Automatic positioning of lubrication points
The automatic positioning of lubrication points that would normally have to be done
manually by visual checks is now performed automatically. A simple touch of a button in eachunit makes the lubrication points appear automatically and reduces the lubrication timerequired.

(3)

Automatic plate nip checking
The nip produced when the ink form rubber roller (water form roller and ink form rollers
X, Y, and Z) is compressed on the plate cylinder is extremely important to maintain the print
quality and stabilize the ink transfer to the plate cylinder. While checking the nip width of theink form roller was generally a manual procedure performed after a problem occurred, that is
now performed automatically on a regular basis so that the ink form roller nip width of eachprinting unit will be printed on the sheet (Figure 3). This improves the control of the press nipwidth.

(4)

Elimination of the plate bending
The plates in an offset press are mounted on the plate cylinder job-by-job to change theimage to be printed. In the past, it was necessary to bend one side of the plate before mounting;however, this has now been eliminated because the plate-locking device has been improved(Figure 4). This means that the time required for plate bending (30 s/unit) can be eliminated,and plate benders are no longer necessary.

Figure 3 Result of printing on sheets with
automatic plate nip checking function

Figure 4 Plate bending(5) SimulChanger
With conventional presses, it is necessary to change the plate for every color unit because thephase of the cylinders for each color printing unit differs when printing. However, full-color
simultaneous plate changes are now possible by matching the phases of all plate cylinders whenchanging the plate. This reduces the time required to change the plate from 4 min to 75 s for a
four-color offset press. The 75-s time required for the plate change does not depend on the numberof printing units, and thus increases the time efficiency of the multi-color offset press (Figure 5).

Figure 5 Full color simultaneous plate changing sequence|4. Updated design
The DIAMOND V3000 has light-emitting diodes on the operator side of the printing unitthat indicate the status of the press. These were added at the same time as the above improvements(Figure 6).

Mitsubishi Heavy Industries Technical Review Vol. 46 No. 1 (Mar. 2009)47|5. DIAMOND V3000 series
In addition to the straight printing press (LX series, Figure 7), a dedicated one-passperfecting press (TP series, Figure 8), and a convertible perfector (R series, Figure 9) have been
added to the DIAMOND V3000 series lineup to meet the demands for various printing needs.

Figure 6 Indication of press status using
light-emitting diodes

Figure 7 DIAMOND V3000LX

Figure 8 DIAMOND V3000TP

Figure 9 DIAMOND V3000R|6. Conclusion
The straight printing press was rolled out as a part of the DIAMOND V3000 series at theInternational Graphic Arts Show 2007 (IGAS 2007) held in Japan in September 2007. The
dedicated one-pass perfecting press and the convertible perfector were exhibited at the world’slargest printing equipment exhibition, DRUPA2008, in Germany in June 2008. This equipment wasvery well received because of its innovative productivity improvements and styling.
This equipment received the Japan Society of Industrial Machinery Manufacturers Prize atthe 38th Industrial Machinery Design Award ceremony sponsored by the Nikkan Kogyo Shimbun,Ltd., on July 29, 2008. On November 6, 2008, the equipment also received the Gold Award at the2008 Good Design Award ceremony sponsored by the Japan Industrial Design Promotion
Organization, as well as placing 5th out of 3023 in the Good Design category.
MHI will continue to be sensitive to market needs so it can provide new products to its
customers as their requirements develop.

Authors
Shinichi Fujimoto
Deputy General Manager,
Printing Press Engineering
Department,
Paper & Printing Machinery
Division

Yasuhiko Hirata
Manager,
Production Department,
Paper & Printing Machinery
Division

Yoshiro Matsuura
Manager,
Printing Press Engineering
Department,
Paper & Printing Machinery
DivisionHajime Yagi
Manager,
Printing Press Engineering
Department,
Paper & Printing Machinery
Division

Yasuhiro Mochizuki
Printing Press Engineering
Department,
Paper & Printing Machinery
Division

Hitoshi Hirose
Printing Press Engineering
Department,
Paper & Printing Machinery
Division