Development of a New
Sheet-fed Offset Press, the“DIAMOND V3000” Series
SHINICHI FUJIMOTO*1YASUHIKO HIRATA*1

YOSHIRO MATSUURA*1

HAJIME YAGI*1
YASUHIRO MOCHIZUKI*1

When the sheet-fed offset press was developed the main focus was on speeding up the printing process. However, with the recent
state of product diversification and the trend towards smaller lot runs, the speed-up offered by a sheet-fed offset press does notnecessarily result in increased productivity. The DIAMOND V3000 sheet-fed offset press was developed to realize substantial
productivity improvements. In the past, the operation rate was improved through shortening the make-ready time and improving themaximum printing speed. The DIAMOND V3000 minimizes the required down time and improves the operation rate not only by
shortening the make-ready time but also by reducing the time required for maintenance and checking. By modifying the appearanceof the press and tidying up the arrangement of pipes and cables, the press status can be easily determined from an LED panel. TheDIAMOND V3000 was exhibited in Japan in September 2007 and in Germany in June 2008. We will explain the advantages of thenew press in this report and will promote its sales in the future.

runs, the down time of a press is relatively long, which
lowers the operation rate (see Fig. 1). Presses are shutdown
to allow for make-ready time, adjustment, cleaning, andmaintenance. To reduce these shutdown factors, various
improvements were made to the DIAMOND V3000, such as
the realization of some lubricant-free components, and theintroduction of a design that provides for easier lubrication,cleaning, and check ing/adjustment (see Fig. 2). We
describe the main advantages of MHI's new printing press,the DIAMOND V3000, in the following sections.

1. Introduction
W hen the sheet-fed of fset press was developed, themain focus was on speeding up the printing process. Eventhough Mitsubishi Heav y I ndust r ies, L td. ( MH I ) has
realized 13,000 sph with the MITSUBISHI 3F, and 16,000
sph with the DIAMOND 3000, the resulting speed-up does
not necessarily improve productivity due to the recent stateof product diversiﬁcation and the trend towards smaller lotruns. The DIAMOND V3000 press was developed for suchsituations, and is intended to realize substantial productivity
improvements.

2. Concept of the DIAMOND V3000

DIAMOND V3000 development approach

The development concept of the DIAMOND V3000 wasa “Net Production Nets Profits.” With the recent state ofproduct diversification and the trend towards smaller lot

Cleaning time
Adjustment time

PurposeMeans

Improved
maintenanceEasier lubrication

Shortened
make-ready time

Maintenancetime

Easier inspection andadjustment
Easier make-ready tasks

Make-ready time
Beforeimprovement

Elimination of loss due
to printing errors

OthersPress
down time

Printing time

Easierperiodical cleaning

Modified tidying tasks
Stabilized quality

Improved
operability and safety

Afterimprovement
Greater printing time

Improved
work environment
Visualized press status

Fig. 1 Times for various tasks performed during daily work

Fig. 2 DIAMOND V3000 development approach*1 Paper & Printing Machinery Division

Mitsubishi Heavy Industries, Ltd.
Technical Review Vol. 45 No. 3 (Sep. 2008)47

(5) Simultaneous implementation of ink cleaning and impression cylinder cleaning(7) Bender-less plate clamp(8) Fully automatic all-color simultaneous plate changer
Delivery(3) Automatic plate nip checking(4) Support of easier roller pressure adjustment

Printing units(2) Automatic positioning of lubricating points(6) Shortening the make-ready process timeFeeder(1) Lubricant-free bearing/torsion bar for the gripper shafts

Fig. 3 Major productivity improvement items(3) Automatic plate nip checking
The nip between the ink form roller and plate cylinder
is very important with respect to the printing quality. The
nip width is checked by contacting the ink form roller withthe plate cylinder and measuring the nip transferred onto
the plate cylinder. The DIAMOND V3000 automatically
performs this task for each printing unit, which was carriedout by the user in the past, and prints the nip between theplate cylinder and form roller onto the paper (see Fig. 4).
As a result of this automation, the user is able to check thenip periodically throughout the printing process rather thanfollowing up after a printing quality problem occurs. At thesame time, the user can perform periodical and numericalnip control tasks by printing and outputting the nip onto thepaper, thereby improving the control of the printing press.
(4) Easier roller pressure adjustment
The nip between the ink oscillating roller and the ink
form roller is also important with respect to the printing
quality. Conventionally, the stripe-shaped nip on the ink
oscillating roller was measured when adjusting the roller
pressure. Experience was required to judge from whichroller the nip came because multiple nips contacted oneroller. For the DIAMOND V3000, the positioning of thenip location on the ink oscillating roller is performed in a
speciﬁed sequence by pushing a button on each printing
unit, in the same manner as the automatic positioningof the lubricating points. Even an operator with lessexperience can easily judge from which roller the nipappears (see Fig. 5).

3. Productivity improvement items
We made various improvements to substantially increase
the productivity of the press. Here, we will explain the main
productivity improvement items (see Fig. 3).
(1) Lubricant-free bearing/torsion bar for the gripper shafts
A sheet-fed offset press transfers paper by delivering itfrom cylinder (impression cylinder/transfer cylinder) tocylinder with a gripper. For the DIAMOND V3000, theamount of lubrication around the gripper was reduced by• adopting a lubricant-free bearing for the gripper shaft,and• replacing a coil spring installed on the gripper shaft
with a torsion bar.
Owing to elimination of these two items, lubricationthat was required at 120 locations once every two weeks
has been eliminated, and there is no longer a concern oversplattering excessive grease onto the sheet, which was aproblem with previous sheet-fed presses.
(2) Automatic positioning of lubricating points
The cylinder must be rotated to a specified position
during lubrication. The DIAMOND V3000 automatically
positions the lubricating points, a procedure performed
visually by the user in the past. When a button on each
unit is pressed, the cylinder rotates to the lubricating
position, thereby enabling the work to start and reducing
the amount of time required.

Water form roller
Ink form roller ZLK

Ink form roller YX
Push
positioning
buttonInk form roller W

Fig. 4 Printing results using the automatic plate nip checking

LK

X

W

W

Ink form roller X

LK

Nip
betweenK and WXW
Push
positioning
buttonNipbetween
K and X

Fig. 5 Movement using the easier roller pressure adjustment

Mitsubishi Heavy Industries, Ltd.
Technical Review Vol. 45 No. 3 (Sep. 2008)48

(5) Simultaneous implementation of ink cleaning and blanket
cleaning
I nk clea ning, bla nket clea ning, a nd impression
cylinder cleaning must be performed after completinga printing task. In the past, ink cleaning and blanket
cleaning were carried out separately. They are carriedout simultaneously for the DIAMOND V3000 so that thepress downtime between ink cleaning and impression
cylinder cleaning is eliminated. T his shor tens thecleaning time by 20 % (see Fig. 6).

Conventional :with bending

DIAMOND V3000 :without bending

Fig. 8 Existence of plate bending
Cleaning/tidying task time comparison
11 minutes
30 seconds

DIAMOND 3000
Ink cleaning

Blanket cleaning(7) Bender-less plate clamp
In an offset printing press, a plate is attached to theplate cylinder. The pattern to be printed changes foreach job. In the past, one side of the plate was bent before
attachment. This bending task has been eliminated bychanging the plate-fixing device (see Fig. 8). Thus,
the working time for the plate-bending task has been
eliminated (30 seconds/color), and a plate bender is nolonger required.
(8) Fully automatic all-color simultaneous plate changer
In the past, the impression cylinder for each printcolor had a different phase during printing. The platechanging task was therefore carried out for each color.
However, the DI A MOND V3000 realizes an all-color
simultaneous plate change by synchronizing the phasesof the impression cylinders during the plate change. This
shortens the required change time to 75 seconds fromthe 4 minutes it took to change the plates of a four-color
press. Because the change time (of 75 seconds) no longer
depends on the number of printing units, the amount oftime saved increases with the number of printing colors

Impression cylindercleaning

DIAMOND V3000
Ink cleaning
Blanket cleaning

Impression cylindercleaning
9 minutes

Fig. 6 Effect of simultaneous cleaning(6) Shortening the make-ready process time
We improved the conventional simultaneous makeready process by• eliminating the press stop bet ween cleaning andprooﬁng, and• performing the ink key preset and blanket cleaning
simultaneously (see Fig. 7).

Test printing

DIAMOND 3000
Ink preset

Operation speed

DIAMOND V3000

Cleaning

Press stop

Press stop

Test printing
Time saved

Ink preset+ cleaning

Lowest speed

Fig. 7 Effect of control review

Mitsubishi Heavy Industries, Ltd.
Technical Review Vol. 45 No. 3 (Sep. 2008)49

Adjustment ofplate cylinder phase

Adjustment ofplate cylinder phase

Fully automatic plate change
New plate

Old plate

Plate cylinder
Switchthe plate cylinder phasefrom printing status
to the same phase.

Simultaneous removal ofold plates and installation of
new plates for all colors.

Return phases
to printing status
after completion ofplate change.

Fig. 9 Sequence of simultaneous all-color plate change

used. Figure 9 shows the sequence followed during thesimultaneous all-color plate change.

(2) Press arrangement
In previous press designs, devices that required
periodic maintenance were installed on the press driveside. But access was difficult because numerous wires
were routed on the ﬂoor surface, resulting in confusion.
For the DIAMOND V3000, a wiring rack was installedon the drive side, eliminating wiring on the floor. Also,
the workability of wash ﬂuid was improved and the area
underneath the drive -side cat walk was tidied up by
moving the cleaning device tank, which requires frequent
maintenance, to a position underneath the operation-sidecatwalk.

4. Design refurbishment
The appearance and operation panel of the DIAMOND
V 3 0 0 0 we r e a l s o mo d i f ie d t o p rov ide t he fol low i n g
improvements.
(1) LED indication of press status
LEDs allocated on the operations side of the printing
component indicate the press status and accent thepress design. They are normally not illuminated. Whenanomaly occurs or the press is undergoing cleaning orpreset task, they change color and blink according toa prescribed pattern to indicate the problem and press
status (see Fig. 10).

5. Conclusion
A single - side DI A MOND V 30 0 0 pr int ing press was
publicly exhibited at the International Graphic Arts Show2007 (IGAS 2007) held in Japan in September, 2007, anda dedicated one-pass perfecting press and single/doubleside combined-use press were exhibited at DRUPA 2008,
the largest printing material exhibition in the world, held inGermany in June, 2008. Visiting customers appreciated theproductivity improvement items and overall design.
We will continue to predict market trends and develop newproducts to meet customers’ needs in the future.

Shinichi Fujimoto

Yasuhiko Hirata

Hajime Yagi

Yasuhiro Mochizuki

Yoshiro Matsuura

Fig. 10 Indication of press status by blinking LED

Mitsubishi Heavy Industries, Ltd.
Technical Review Vol. 45 No. 3 (Sep. 2008)50