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PRESSES AND PRESS EQUIPMENT 13

Narrow-Web Presses

arrow-web flexo has most

recently been defined as any

web width less than 20" (508

mm). While this is an arbitrary

designation, it will serve as a

definition for this chapter. The

vast majority of narrow-web presses, how-

ever, are 16" (406 mm) or less, and most are

10" (254 mm) or smaller. However, changing

market conditions and the need for greater

productivity have created a definite trend

toward the use of wider presses. Web widths

of 10" (254 mm) and 13" (330 mm) have sup-

planted the old standards of 6" (152 mm) to

8" (203 mm) web widths. Presses with 18"

(457 mm) to 20" (508 mm) web widths are

becoming more common.

Narrow-web flexography is also character-

ized as a rotary process with multiple in-line

converting functions. Variable print, or

repeat length, capability is a critical feature

in the markets served by narrow-web equip-

ment. With alternate printing processes, vary-

ing repeat is often accomplished with an

intermittent web motion. The elegant sim-

plicity of the flexo ink system, low-cost plate

cylinders, and the ease and cost effectiveness

of processing plates in a variety of sizes,

make an intermittent or platen type of sys-

tem unnecessary on narrow-web flexo press-

es. Plate cylinders are easily and economi-

cally changed on narrow-web presses, pro-

viding the ability to alter the repeat length

while maintaining rotary printing. Typical

narrow-web flexo presses have a print repeat

range from approximately 4" (101 mm) to 24"

(609 mm) in 0.125" (3 mm) increments.

It is rare for a narrow-web flexo press to

be limited to simply printing. Typical appli-

cations will include some form of in-line

converting operation, such as die-cutting,

slitting or laminating. The ability of narrow

web presses to do multiple operations in-line

at high speeds provides tremendous produc-

tion efficiencies and cost savings to users.

The converting operations performed on

narrow-web presses are also usually accom-

plished by rotary means. However, platen, or

flatbed, die-cutting can be used, and foil for

stamping can also be fed intermittently.

DEVELOPMENT AND GROWTH

The origin of narrow-web flexography is

usually placed in the period immediately

after WW II. At that time, Mark Andrews Sr.

(1904-1980), the founder of Mark Andy, Inc.,

made his first presses for printing on the

then new product, “Scotch Tape.” Others

may have made similar equipment prior to

this but, unquestionably, Andrews was the

first to begin the sustained manufacture and

marketing of narrow-web flexo presses.

Flexo then was still called the “aniline”

process, named for the aniline dies in the

inks. These initial presses were designed to

sit on a workbench or table and were used

for making labels from self-wound, self-

adhesive tapes. Web widths were 2" to 4" (50

mm to 100 mm).

Andrews is also credited with another

innovation that has shaped the narrow web

flexo industry: the development of rotary die-

cutting and its integration into narrow-web

presses. Initially, these rotary dies were used

for perforating tapes. As pressure-sensitive

roll label markets emerged, the entrepre-

neurs building that industry recognized the

14 FLEXOGRAPHY: PRINCIPLES & PRACTICES

advantage and cost effectiveness of in-line

printing and die-cutting on narrow-web flexo

equipment. These early innovators forged a

bond between pressure-sensitive roll labels,

flexographic printing and in-line rotary die-

cutting that has facilitated and forced growth

and advancement within each of the tech-

nologies and built them into world class dis-

ciplines.

The explosive growth of pressure-sensitive

labels (estimated to have a value of $10 bil-

lion in North America by the year 2000) has

fueled the growth and development of nar-

row-web flexography. However, narrow-web

presses are used for a vast variety of prod-

ucts in addition to pressure sensitive labels.

Many of these products are other forms of

product identification or promotion such as

tags, in-mold labels, sleeves and cartons.

Lottery pieces and tickets for everything

from sporting events to transportation and

turnpike usage are common narrow web

applications. Medical and pharmaceutical

packaging is produced on narrow-web press-

es, as are foil and paper lids. Increasingly,

narrow-web presses are used for manufac-

turing folding cartons and flexible packaging.

Advantages

Narrow-web flexography has many ad-

vantages that make its economics very com-

pelling in a world of higher quality, cost-

effective productivity, and shorter, more fre-

quent runs. In-line processing reduces the

time and costs associated with multiple pro-

cessing steps, such as those that occur with

the sheet-fed offset manufacturing of folding

cartons. This advantage is reinforced with

the multitude of tasks that can be combined

on narrow-web presses. These tasks range

from corona treatment to multiple forms of

graphic imaging, including variable data,

overprint varnishes and laminates. In-line

die-cutting, hole punching, perforating,

creasing, embossing and folding can also be

done on narrow-web flexo presses. Multiple

webs can be processed, married together

and delivered in roll, sheet or stacked for-

mats. The multiplex character of narrow-

web presses gives their users a strong cost

advantage on a wide variety of products.

In addition to the time and labor saved by

performing multiple operations on a narrow-

web flexo press, material waste is also

reduced. The spoilage associated with han-

dling and moving of the work in process is

eliminated, as is the scrap generated by mul-

tiple setups in the manufacturing pro-

cess. Since the material is typically the

largest cost element in the finished product,

waste reduction can have a tremendous

impact on profitability.

Another advantage of narrow-web flexo

presses is their ability to be set up and

changed-over quickly. Part of this efficiency

is due to the nature of flexo printing com-

pared to other technologies, and part is

inherent from being smaller than their wide-

web counterparts. Narrow-web press manu-

facturers have also made setup and change-

over efficiency a key element of their

designs. This concerted effort by press

designers has dramatically reduced the time

required to set up narrow web presses, even

as the complexity and difficulty of the

work performed on them has increased.

Sophisticated change out and clean up pro-

cedures are increasingly utilized by convert-

ers to achieve maximum productivity of

their equipment. These innovations have led

to makeready times of 10 minutes or less for

changing from one six color job to another,

on state-of-the-art narrow web presses. This

quick changeover includes plate rolls, ink

fountains, anilox rolls, metering system,

material and die changes.

The final element that gives narrow-web

flexo a significant advantage over competing

technologies is the quality being produced by

narrow-web converters. Advances in pre-

press, plate, anilox, ink and press technolo-

gies have been eagerly embraced by narrow-

web converters and combined into a world

class printing technology. While each printing

process has its own unique set of strengths

and weaknesses, flexo has made tremendous

progress in overcoming its weaknesses and

further advancing its strengths. As a conse-

quence, process work of 200 and 225 lpi is

now being printed on narrow-web flexo

presses, while solids are richer and smoother

than ever before.

TYPES OF NARROW-WEB PRESSES

There are four basic design styles of nar-

row-web presses: central impression, in-line,

stack and platform. These presses are distin-

guished from one another in the first

instance by their web paths, as determined

PRESSES AND PRESS EQUIPMENT 15

f A typical narrow-web

four-color CI press.

Among the features

that make it popular is

its relatively low cost,

small footprint, and

easy-to-use controls

and accessories.

by the spatial orientation of their printing sta-

tions. From this difference, a number of

other characteristics are derived.

Central Impression Presses

The earliest narrow-web flexo label presses

were central impression, and this design has

remained popular through the years. Narrow-

web central impression presses, like their

wide-web counterparts, are characterized by

the location of all the printing units around a

common impression drum (Figure

Unlike wide-web central impression presses,

the typical narrow-web CI press is three or

four colors. Satellite stations, not located on

the central drum, can be added to obtain five-

or six-color capability.

Narrow-web central impression presses

A Laminate

B Laminate Waste Rewind

C Die Cutting

D Main Dryer

E Die Cutting

F Waste Rewind

G Rewind 2

H Rewind 1

I Unwind

J Common Impression Cylinder

K Dryer Between Station

L Print Unit Casette

16 FLEXOGRAPHY: PRINCIPLES & PRACTICES

are relatively inexpensive and take up a

small amount of floor space. They typically

do not have sophisticated controls and

accessories, making them easy to operate

and maintain. These characteristics make

the design popular with smaller and start-up

companies, as well as with larger converters

needing additional capacity for low-end

work. This style of press is also often used

for training in educational institutions.

Because the web is captured on a com-

mon cylinder and not subject to tension

fluctuations as it is transported from station

to station, central impression presses hold

excellent color to color register. They are

well suited for printing difficult to control

materials, such as tapes, highly extensible

films and cloth.

The typical narrow-web central impression

press has a web width range of 6" (152 mm)

to 20" (508 mm). This narrow width, and the

limited number of colors on typical narrow-

web CI presses, have restricted their use in

the flexible packaging market. However, in

response to changes in the flexible packaging

market and its need for equipment better

suited for shorter run lengths, traditional

wide-web press manufacturers have intro-

duced narrower versions of their wide-web

central impression presses. These presses

are typically six to eight colors and have a

web width of 16" (406 mm) to 24" (609 mm).

While falling within the range defined as nar-

row web, the design of these presses is heav-

ily influenced by their wide-web origins, and

the reader is directed to the wide web chap-

ter for more information on them.

In-line Presses

In-line presses, as their name implies, have

their printing stations oriented horizontally

to one another (Figure

). Each printing

station has its own impression cylinder.

These presses are appreciably longer than

central impression presses, but are also

more versatile and provide the operator with

greater accessibility to the printing stations.

More than 75% of the narrow-web presses

sold today are in-line designs.

In-line presses are manufactured in a full

range of web widths, from 7" (178 mm) to 24"

(609 mm). They are often modular, i.e.,

designed to allow the buyer to specify the

number of print stations required, and, if nec-

essary, to add stations at a later date. The

number of print stations on an average in-line

press has increased over the years. Six to

eight colors are now typical, but 12 or more is

not uncommon. Even on the largest in-line

presses, register tolerance is typically less

than ±0.005" (0.13 mm) over a specified num-

ber of repeats.

In a typical narrow-

web in-line press,

printing stations are

configured horizontally,

providing versatility

and accessiblity to the

printing stations.

D D D

A Unwind

B Web Inverter

C Print Units

D Die Cutting

E Waste Removal

F Lamination

G Rewind

H Between Station Dryers

CCCC

H H H

The range of available web widths, and the

number of print and converting positions

possible with in-line style presses, make

them very adaptable to a wide variety of

uses and markets. Their open, accessible

design allows many accessories to be added

to them for specialized requirements. Thus,

most of the narrow-web flexo presses used

for folding cartons, flexible packaging, lot-

tery tickets and coupon applications, are of

the in-line design.

There are many design variations within

the category of in-line presses. Some are

cantilevered, i.e., without a framework on

the operator’s side of the press, while others

are fully framed. All in-line presses have to

transport the web from one station, or mod-

ule, to another. However, the web path to

accomplish this may vary dramatically,

depending on the location of the interstation

dryers. Likewise, the level and sophistica-

tion of the press controls range from basic

manual, mechanical functions to nearly fully

automated presses.

Stack Presses

Narrow-web stack presses are character-

ized by the vertical relationship of their print

stations, and they are sometimes referred to

as “vertical in-line” presses (Figure

Stack presses can also have the print sta-

tions oriented in an inverted “U.” Like the

central impression press, the stack press

takes up a small amount of floor space. Like

the in-line press, the stack press has individ-

ual impression rollers. Stack presses are

PRESSES AND PRESS EQUIPMENT 17

A typical four-color

narrow-web stack

press, also known as a

vertical in-line press,

can be configured with

as many as eight print

stations.

Air Unwind

Print Station

4th Print Station or

Coating Station

Single

Rewind

Waste Windup

Sheeter

Double

Die

18 FLEXOGRAPHY: PRINCIPLES & PRACTICES

usually manufactured with four, six or eight

print stations.

In the narrow web industry, due to the

need for larger registration tolerances on

stack presses, they have not been as popular

as in-line and central impression presses.

However, stack presses do provide a good

solution to the converter with restricted

space and requiring more flexibility than can

be obtained with a central impression press.

Also, there is more distance for drying

between print stations on narrow-web stack

presses than on CI presses. This additional

drying time allows some job layouts to run at

a higher speed on a stack press than on a

central impression press.

Platform Presses

Platform presses are a recent develop-

ment in narrow-web flexo. Unlike CI, in-line

and stack presses, a platform press is not

distinguished from other presses by its web

path. Instead, platform presses are unique in

their ability to move processing and convert-

ing functions from one location to another.

Narrow-web flexo is characterized, in part,

by its ability to perform multiple printing

and converting functions. Other narrow-web

presses allow the converter to define the

position of various functions of the in-line

process at the time of manufacture, but they

are then, essentially, fixed in location.

Platform presses take this attribute to the

next level by allowing the converter to

quickly rearrange the press to the most

effective in-line process configuration to

efficiently run the job at hand.

Platform presses are oriented in an in-line

fashion. In addition to allowing printing and

converting functions to be repositioned,

platform presses often will combine a num-

ber of printing technologies, which can also

be positioned where needed. Rotary screen,

lithographic offset and foil stamping are

common printing technologies that may be

combined with flexo on platform presses.

The need for platform presses arises from

three fundamental market developments.

First is the increasing variety and complexi-

ty of products produced by narrow-web con-

verters. Fixed position presses, either in

generic or specialized formats, are difficult

to adapt to these rapidly developing and

changing requirements. A second catalyst

for the development of platform presses

comes from heightened and changing graph-

ic requirements. Flexography has dramati-

cally increased the range of graphics that it

can reproduce. However, the graphic design

of some labels and packaging can be most

efficiently reproduced only by combining a

number of printing technologies. As narrow-

web presses are used to produce labels and

packaging for an increasingly broad array of

products, the need for combining print tech-

nologies will increase.

The final development leading to platform

presses is the increase in pricing pressures

among converters, which has in turn caused a

need for efficient production techniques to

control and contain costs. It has also led to

more customized equipment needs as con-

verters develop unique and profitable prod-

ucts for niche market opportunities. Platform

presses provide “on the fly” customization to

meet these changing requirements.

PRODUCTS PRINTED

The flexibility of narrow-web presses, the

economics of single-stage production and

the ingenuity of narrow-web converters

have resulted in a tremendous variety of

products being produced on narrow-web

equipment. Nearly any product substrate

with a thickness between 0.001" (0.025mm)

and 0.024" (0.6mm) that can start as one or

more rolls of material, is a candidate for con-

version on a narrow-web press. Some exam-

ples include:

Folding Cartons. This product can be printed,

creased, blanked out and delivered in a sin-

gle pass on narrow-web presses. Other

examples of similar applications are paper

cups and sidewalls for dairy product con-

tainers.

Business Forms and Form/Label Combinations.

To produce form/label combinations, a dual

unwind is required together with some form

of adhesive applicator.

Lids and Closures. Foil lids for juices and

yogurt cups, for example, can be converted

on narrow-web equipment. Likewise, paper-

board lids, such as for ice cream containers,

can be produced in a single pass on narrow-

web presses. These lids often include a lam-

inated viewing window that requires blank-

ing out the window, applying a patterned

adhesive, laminating and then diecutting the

laminate. As with folding cartons, the foil

and paperboard lids are blanked out and

delivered on a conveyor or stacker.

Tickets. A variety of tickets can be converted

on narrow-web equipment. Depending on the

use of the ticket, these may require high-

quality graphics, as for sport and entertain-

ment venues, or precision-cut lengths for

automatic dispensing of turnpike tickets.

Lottery tickets require multiple print and

coating stations and the use of special inks.

Increasingly, security and anti-counterfeit

features are incorporated into tickets for

authentication and tracking.

Tags. The retail industry uses a tremendous

number of tags in a variety of forms, includ-

ing hang tags, static-cling tags and pressure-

sensitive tags. All of these can be produced

on narrow-web presses.

Flexible Packaging. Wraps for beverage con-

tainers and other products are printed roll to

roll on narrow web presses, as is packaging

for food products. Tubes, such as those used

for toothpaste and gel containers, are also

produced on narrow web equipment.

Coupons and Information Booklets. Instant

redeemable coupons and extended informa-

tion booklets are increasingly popular pro-

motional and information vehicles. They

require multiple unwinds, the ability to print

and die-cut the webs individually, and the

application of adhesives. All of this is done in

a single pass on narrow-web presses.

Pressure-Sensitive Labels. The most common

use of narrow-web presses is to produce

pressure-sensitive labels. These products

are used for product promotion and identifi-

cation (prime labels), ingredient and usage

instructions (secondary labels), material

tracking and control, and promotional

pieces, to name just a few examples.

Self-wound, Self-adhesive Tapes. Tapes are

used for promotion and identification of a

number of products, including tires, metal

rods and conductive wires.

Other. Other uses growing in popularity

include medical and pharmaceutical packag-

ing, in-mold labels, and shelf markers and

shelf talkers.

THE NARROW WEB PROCESS

Since most narrow-web presses are in-line

presses, we will use that design, generally, for

the purposes of describing the components

of narrow-web equipment. The description

will also be, for the most part, of a generic

press for pressure-sensitive labels. The pri-

mary elements of these presses are:

• unwind;

• in-feed and tension control;

• print stations;

• drying and curing;

• die-cut stations;

• waste removal; and

• delivery.

Unwind

The unwind of a modern narrow-web press

can, generally, handle rolls up to 1,000 lbs. or

40" (101 cm) in diameter. A roll loader will

often be built into the press to assist in han-

dling large rolls. A splicing platform and web

guide are also usually included in the unwind

module. The web guide may be a manual

PRESSES AND PRESS EQUIPMENT 19

20 FLEXOGRAPHY: PRINCIPLES & PRACTICES

device, but more typically is automatic.

Automatic web guides may be hydraulic or

pneumatic and may use an optic, sonic or

pneumatic sensor.

Unwind Tension. An unwind brake is used to

apply tension to the web as it is unwound

from the roll. The braking device, which may

be pneumatic, magnetic or electric, is me-

chanically coupled to the unwind core-hold-

er to restrict its rotation. The brake may

apply either a constant, fixed force, or it may

vary the force to obtain a constant tension.

Constant-torque systems, which apply a

fixed force, are efficient only with smaller

diameter rolls, such as those less than 15"

(38 cm) in diameter. Since the braking force

is generally applied at the core-holder, the

force required to obtain a given tension is

greater at larger diameters than at smaller

diameters. Consequently, if large diameter

rolls are used with constant-torque brakes,

the press operator must periodically adjust

the brake as the roll diameter changes.

Constant-torque systems are usually used

only on small central impression presses

with limited roll sizes, and in situations

where the printing and converting accuracy

is not critical.

Constant-tension systems continually

adjust the torque of the brake as the roll

diameter changes. This can be done either

by sensing the diameter of the roll or by

measuring tension changes. Sonic and opti-

cal sensors are the most common methods

used on narrow-web presses to monitor roll

diameter. In some cases, a follower roller

maintains physical contact with the roll of

material. Tension-responsive systems are

also commonly used on narrow-web press-

es. These systems may employ a load cell to

measure absolute web tension, or a dancer

system that uses a counterbalance measure

of tension. The typical narrow-web dancer

system will be pneumatically loaded against

the tension created by the unwind brake. An

advantage of the dancer system is that it will

accumulate and release material if neces-

sary, such as with irregularly wound rolls or

during speed changes.

Unwind stands capable of handling rolls

greater than 40" (101 cm) in diameter can be

used with narrow web presses. These stands

are often supplied with presses purchased for

folding carton applications. In some

instances, these larger roll stands will incor-

porate multiple unwind stands with automat-

ic splicing to provide continuous, nonstop

production. Automatic splice stands are also

used for high-volume label production. These

stands must make butt-splices to avoid dam-

age to dies, while allowing continuous wind-

ing of the die-cut waste matrix. Multiple

unwind modules without automatic splicing

are also commonly used on narrow-web

presses for applications that require lamina-

tion of multiple webs, including coupons and

form/label combinations.

In-feed and Tension Control

Some narrow-web presses use only the

tension created by the unwind brake to con-

trol the web as it enters the process area.

However, most have some form of in-feed

pacing in addition to an unwind tension sys-

tem. The in-feed pacing system will have a

driven roller and a rubber nip roller. In some

cases, the system will also have a tension

monitoring device and regulating controls.

Those systems without a monitoring and

control loop are called “open loop” systems.

The driven roller in these systems will have

a fixed velocity relative to press speed.

“Closed loop” systems, those with a moni-

toring and control system, allow a press

operator to select a web-tension level that is

to be maintained. This is done with an elec-

tronic feedback system, which monitors the

tension of the web and compares it to the

selected tension level. Depending on the sys-

tem, a constant tension is maintained by

varying the velocity of the driven roller or of

the braking torque applied to it.

Some narrow-web presses can vary the

velocity of both the in-feed and the exit pac-

ing rollers. This capability allows the press

operator to alter tension while maintaining a

constant amount of material passing through

the press on each revolution. Some applica-

tions, such as EDP labels, require an exact,

specified throw length, or spacing of the

labels and feed holes. The capability to alter

tension without affecting throw length is very

important to converters of these products.

In-feed pacing systems are used to create

an initial web tension and to control the web

as it enters the press. Maintaining tension

through the press is the function of the exit-

pacing roller, and, to a lesser extent, all of

the driven rollers in the press. Web control is

obtained on all web presses through tension.

H o w e v e r, as the web passes through the

press and over rollers, it loses energy due to

friction, inertia and deformation. These

energy losses reduce web tension. To bal-

ance the energy losses and maintain ade-

quate tension through the press, the exit-

pacing roller will, typically, have a higher

velocity than the other rollers in the press.

Some press designs will have a slight, but

precise, gradation of the velocity of all dri-

ven rollers. The gradient can be introduced

by minute changes to the diameter of the

rollers to alter their surface speed, or by use

of servo motors to regulate roller velocity.

Print Stations

As with any flexo press, narrow-web press-

es use an anilox roll to control the amount of

ink applied to the printing plate. Many nar-

row-web presses are supplied with laser-

engraved ceramic anilox rolls, although

mechanically engraved chrome rolls are also

used. Metering of the ink film is typically

done with a reverse-angle doctor blade in a

two-roll system. In these systems, the foun-

tain roller is used to flood the anilox roll with

ink. The rubber fountain, or doctor, roller

may be driven at a one-to-one ratio to the

press speed, or at a slower ratio. If desired,

the fountain roller, instead of the doctor

blade, may be used to meter the ink. Some

narrow-web presses are designed to use only

a doctor blade and do not have a metering

r o l l e r. Either conventional reverse-angle doc-

tor blades or chambered doctor blade sys-

tems are used in these cases.

Repeat Lengths. Narrow-web presses do not

have a fixed print repeat. A typical narrow

web press will have a repeat range of approx-

imately 5" to 24" (127 mm-610 mm). Also, nar-

row-web presses print on a wide range of

materials with varying thickness. As a conse-

quence, narrow-web presses must allow pre-

cise adjustment of plate cylinders with a

wide range of diameters, to materials of vary-

ing caliper. This is typically done with

“adjusting arms” that move perpendicular to

the point at which the plate cylinder contacts

the anilox and impression rollers. The plate

cylinder is captured in the adjusting arms

with journals or by a rod passing through the

plate cylinder bearings. The movement of the

adjusting arms must be sufficient to accom-

modate the full repeat length range. In addi-

tion to this coarse positioning of the plate

c y l i n d e r, finite adjustments are provided to

establish precise pressure settings between

the printing plate and the anilox roll, and

between the plate and the web. This can be

done either by adjustment of the position of

the plate cylinder relative to ink and web, or

by positioning the plate cylinder to the web

and adjusting the anilox roll position to the

plate. Regardless of the method used, the

mechanism must be rigid to avoid plate-roll

bounce and to maintain the pressure settings

throughout the run. Figure

shows a typi-

cal narrow-web print station.

Registration Adjustment. Because the repeat

length is variable on narrow-web presses,

there is not a constant relationship that

establishes close linear register position

between stations. Consequently, narrow-web

presses provide for both coarse and fine reg-

PRESSES AND PRESS EQUIPMENT 21

22 FLEXOGRAPHY: PRINCIPLES & PRACTICES

ister adjustments. Coarse register adjust-

ments are made in a number of ways on nar-

row-web presses. The most common is by

disengaging the gear of the plate cylinder

from its drive gear and rotating the plate

c y l i n d e r. Another method is to use a high-

speed motor to rotate the plate cylinder. This

method is sometimes used for automatic pre-

the operator positions all of the plate rolls at

the equivalent of top-dead-center, and enters

the repeat length information into a proces-

s o r. The processor calculates the amount

each plate cylinder needs to be rotated, or

offset, to obtain a coarse register position.

Coarse positioning is used to register the

print to within approximately one gear

tooth, typically 0.125". Fine positioning, to

establish precise register, may be a manual

or an automatic function. Fine adjustments

are usualy made through a worm gear to

momentarily change the velocity of the plate

cylinder or die. This adjustment results in a

phase shift of the position of the tooling. The

adjustment range may be a full 360°, or with-

in a prescribed window.

Automatic Register Systems. Automatic regis-

ter systems normally are used with 360° gear-

boxes, but they can also be used with sys-

tems with a restricted adjustment range. Tw o

basic types of automatic register systems are

used on narrow-web presses. One style is a

mark-to-mark system. This style uses one or

more optic sensors to “read” the position of a

series of sequentially printed register marks.

The other style of automatic register system

A typical narrow-web

print station layout.