In the course of its last few miles, the River Elbe links the Hamburg
conurbation to the North Sea. Stade is situated at the halfway point. Zeitungsverlag
Krause GmbH & Co. KG, a newspaper publisher with its own printing center,
resides on the outskirts of this small town in Northern Germany. The company
prints dailies and freesheets for the local town and region on a 32-page
KBA Journal Express web press. This coldset web press was installed in two
stages, with the result that both brush and spray dampening systems are
used. In February 2006, Krause’s BALDWIN Litho Spray World spray dampening
systems were retrofitted with BALDWIN Constant C technology. In the old
days prior to upgrading the system, around ten press stops a week due to
clogged nozzles were the rule. Since the advent of Constant C, the newspaper
press has not been forced to stand still for a single minute due to problems
with the dampening systems. The upshot is a remarkable increase in productivity.
The benefits are most evident in the details: in the KBA press the BALDWIN
Litho Spray World spray bars dampening systems are fitted with eight nozzles
– two for every plate on the cylinder. The distributors overlap
slightly at the edges, so that the first roller in each dampening system
receives an absolutely constant supply of fountain solution.
In the absence of any special precautions, there is always a risk of
clogging due to ink mist or debris building up on press. Partially or
completely obstructed nozzles alter the spray pattern and thus impact
the entire fountain solution supply. Pressroom difficulties and uncontrollable
variations in the final presswork quality are the outcome. BALDWIN’s
Constant C technology gets to the root of these problems. It eliminates
clogging by creating an air curtain that permanently surrounds the nozzle
tips. Pollutants, debris, and ink mist are effectively kept out of the
way of the nozzles. In addition, all nozzles at Krause are given a good
“blow-through” at the end of the production process. This
stops any remaining fountain solution from drying out inside, so that
additional residues never get a chance to settle in the fine tips.
Incrementally upgraded
When Manfred Kriett, head of the printing department, discusses the different
upgrade stages and dampening technologies, he is speaking from experience.
The KBA Journal Express commissioned back in 1991 was initially a single-floor
press with two Y printing units. These units were – and still are
– equipped with brush dampening systems. The expansion of the press
line with a four-high tower in 2002 coincided with the migration of the
Y printing units to a three-high tower for 4/2-color printing. The four-high
tower was ordered with BALDWIN Litho Spray World spray dampening systems
from the outset.
“We always endeavor to keep our noses to the wind of any technological
developments and we were confident that the new spray dampening systems
would benefit us enormously,” says Manfred Kriett commenting on
the original investment decision. “We were unwilling to go for brushes
again because the BALDWIN concept lets us meter the fountain solution
much more finely and transfer it to the dampening rollers and the plates
more evenly. Brush dampening systems also entail a higher risk of contamination
owing to the open water fountains, which provide a fertile breeding ground
for undesirable microorganisms of all kinds.” Kriett urged his company’s
management to invest in a technology that facilitates professional fine-tuning
in addition to simply speeding up on-press development and reducing makeready
waste. “The fact that every nozzle can be individually adjusted
to permit optimum control of the fountain solution supply is a real stroke
of genius. After the press has been running for a while, the heat from
the gearbox radiates from the drive end toward the cylinder, for instance.
The fountain evaporates asymmetrically as a result, leading to a deterioration
in print quality. This used to leave us with huge amounts of waste, whereas
now the water supply via the nozzles to the affected zone is simply increased.
These optimization potentials were a clear argument in favor of spray
dampening systems and BALDWIN was our preferred supplier on account of
the mature technology.”
According to Manfred Kriett, there is also no reason why the Y units
should continue to dampen with brushes for ever more. “As soon as
they become worn to the extent that they need replacing, we will have
no hesitation in purchasing spray dampening systems in their stead.”
Compared to the brush method, spray dampening cuts the Krause printing
center’s waste rate on equivalent printing units by a good 20%.
On-press development with a precisely metered quantity of fountain solution
at just the right temperature is faster and the optimal ink/water balance
is achieved in next to no time.
Small nozzles, big difference
Manfred Kriett explains why his company elected to upgrade the Litho
Spray World spray bars with Constant C in February 2006: “Pressroom
performance regularly suffered because of clogged nozzles in the spray
dampening system and we suspected that the fountain solution additive
was the cause. If we refrained from making full use of the web and produced
without dummy plates, milky deposits were visible on the cylinder. We
guessed it was they that were creating such hard times for our nozzles.
After experimenting with different additives that failed to provide any
clear indication, our attention was drawn to Constant C by our BALDWIN
consultant. Suddenly, all our headaches were gone.”
“Ever since we fitted our Litho Spray World spray bars with Constant
C, the dampening system has worked perfectly. In addition to a significant
reduction in downtimes, we have also noticed a measurable improvement
in print quality. Previously, whenever one of the nozzles clogged during
production printing, we noticed major variations in the fountain solution
supply, causing the ink to smear,” Kriett continues. “Constant
C affords us effective protection against uneven quality. Not only has
the makeready waste that invariably accompanies a stoppage been eradicated,
we also incur no labor costs for cleaning the nozzles. Although the spray
bars are easily accessible, that always used to be considered a tiresome
chore and production was inevitably lost.
High on impact, low on maintenance
The Krause web press is equipped with a total of eight BALDWIN Litho
Spray World spray bars, with a ninth bar in reserve. It took the fitter
one working day to retrofit Constant C and another to complete the fine
adjustments and program the parameters on the control desk. That an upgrade
of this kind must be carried out without interrupting production goes
without saying, according to Manfred Kriett. “We print at least
five newspapers daily as well as two weekly freesheets and we can’t
afford to have the press shut down for long.”
A new interface had to be implemented in a collaborative venture by BALDWIN
and EAE, the electronic equipment manufacturer, to facilitate seamless
communication between the nozzles on the spray bars and the press control
desk. It was integrated without a hitch parallel to the installation of
the Constant C system.
The saving generated by the tremendously extended maintenance cycles
alone has assured the Krause printing center a phenomenal return on its
investment. In the pre-Constant C era, the spray bars had to be removed
and cleaned at least once a fortnight. Today, this time consuming job
is only undertaken every four weeks at the most and the press operator
combines it with cleaning the complete press – not because it is
absolutely essential but simply to avoid taking any risk. The rugged design
of the Litho Spray World’s all-stainless steel spray bars and the
use of highly solvent-resistant sealing materials for all valves and connections
additionally enhances the system’s reliability and lifetime.
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