Chapter 3 Quiz Questions Flashcards
When printing with quickset inks the rigidity rapidly increases during____________. With heatset inks the rigidity increase at ____________.
When printing with quickset inks the rigidity rapidly increases during absorption. With heatset inks the rigidity increases at the chill rolls.
When does heatset ink become completely dry?
When it is off press
Which type of heatset web offset press employs a floating dyer?
Blanket-to-Blanket
Catalytic oxidizers heat the exhaust from a heatset dryer to ______. Thermal oxidizers heat the exhaust to _________.
Catalytic oxidizers heat the exhaust from a heatset dryer to 600-800F. Thermal oxidizers heat the exhaust to 1400-1500F
Web temperature can be controlled at the chill rolls by:
Changing the temperature of the water and changing the rate of water circulation.
Chill roll tacking increases the attraction between the web and the chill rolls by using what?
Electrostatic force
Higher press speed will _______ the dwell time of the web, while longer dryers will ______ the dwell time of the web.
Higher press speed will decrease the dwell time of the web, while longer dryers will increase the dwell time of the web.
The web temperature after the last chill roll should be no more than ___F?
75F
The order that the chill rolls are plumbed goes:
Last to first, and the first chill roll should cool the web by 40-50%
Remoisturizers are used for what type of problems?
Paper growth and static electricity
Do news inks dry by absorption and solidification of resins in the chill roll section?
False
Chill roll over speed should typically be set to?
1-2%
Coated webs normally require ______ dryer temperatures than uncoated webs.
Coated webs normally require higher dryer temperatures than uncoated webs.
What are the three benefits of the sine wave produced by the hot air dryer?
- Improved web control
- Prevention of corrugating wrinkles
- Prevention of web flutter
What is the boundary layer?
It is the thin layer of air that travels with the web as it moves through the dryer.
When using a split web to determine the nose setting, what does an overlap mean?
This means that the former board angle is too low
What are the first set of rollers that follow the former board called?
- Guide rollers
On a combination folder, what is the correct sequence of folds?
Former fold, jaw fold, chopper fold
The guide rollers can be skewed to maintain even _________ on the former.
The guide rollers can be skewed to maintain even tension on the former.
How does a jaw folder deliver a folded signature?
With the spine of the signature out , leading.
What is the correct location of the collect cylinders?
- After the former but before the jaw folder
What is the circumference of a collect cylinder?
It is three times the circumference of the knife cylinder.
On a full web press what would a collect cylinder be used for?
For digest size
True or False a Ribbon folder uses a collect cylinder?
True
What does the double-former fold result in? And what is it common for?
It results in an open head signature and it is common for newspapers
Which type of folder most limits the press speed?
The chopper folder
Which in-line gluing system is similar to a flexo printing unit?
Pattern Gluer
Which perforating device makes angled perforations to direct paper tissues?
Gusset Perforator
The double-chopper combination folder is designed to improve what property of the folder?
The speed
What is the cutoff dimension for a web press that uses the collect feature?
Half the circumference of the plate cylinder
What does the moveable jaw on a jaw folder seize?
It seizes the spine of the signature
What combination of folders is required to create a magazine size signature? With a 34 wide web and 22 cutoff
Former, jaw, chopper
What combination of folders is required to create a magazine size signature? With a 17 wide web and 22 cutoff
Former and Jaw
You are perfecting on a satellite web press where both sides of the web passes through the same printing unit, what is this process called?
Double-ending
Which two factors determine the signature size of a web press, when the signature is opened flat?
- the cutoff
- the width of the cylinders
What term defines a press that uses independent motors controlled via fiber optic links to a central controller?
Shaftless press
Which web offset press configuration requires an S-wrap to print two colours on one side of the web, using a single printing unit?
Blanket-to-Blanket
How many units does a blanket-to-blanket press require to print 4 colours on both sides of the web?
4 units
What are some benefits for using gapless technology in web offset presses?
Quicker makeready, shorter runs, saves paper
What was the name of the first hapless blanket press called?
Heidelberg Harris Sunday press
True or false? Gap less blanket presses do not use bearer contact
True
The blanket circumference is normally the same measurement as what?
Web cutoff
How should blankets be stored?
Flat, face to face
What is caused by excessive plate/blanket squeeze?
Dot gain
What are the parts of a blanket-to-blanket printing unit?
- plate cylinder
- blanket cylinder
- inking system
- dampening system
True or False? When the plate gap is centred in the blanket gap, unwanted ink and water on the plate edges won’t transfer to the blanket
True
What does improper plate bending cause:
- Misregister
- plate slipping
- plate cracking
Which forms do blankets come in?
- prepunched
- premounted onto bars
- gapless blankets
What determines the amount of squeeze between the plate and blanket?
The total thickness of the plate, blanket and packing sheets on both cylinders
If the web is unwinding too _____ the dancer roll will rise, causing ______ braking to be applied.
If the web is unwinding too slow the dancer roll will rise, causing less braking to be applied.
What is contained in the splicing arm of the flying paster?
A knife and a pressure roller
What is the proper combination of three infeed metering rollers on a web press?
- 2 driven steel rollers and 1 non-driven rubber roller
Which splicing method can a splice be made while the press is running at printing speed?
- the flying paster
- zero-speed method
A zero-speed splicer can make Both a ____ & ____?
A lap splice and butt splice
What uses variable control to control the flow rate of the web?
The infeed metering rollers
The strongest, most positive control of the web occurs at which nip point?
Printing units
On a box-tilt device, which rollers are fixed and which are movable?
1 and 4 are fixed, 2 and 3 are moveable
What are the different types of web break detectors?
- Mechanical
- Optical
- Pneumatic
Which is the most common type of web break detector?
Optical
What does the term “fan-out” describe?
Relative Print Width
Bustle wheels are used to?
Bring the edges of the web closer
On a flying paster splicing system, what actions occur when the first butt switch is activated?
- The acceleration belt drops on the new roll
- The next roll rotates into splicing position
- The splicing arm presses against the surface of the expiring roll
Which splicing method requires the lead edge of the new roll to be held by a policing roll, close to the expiring roll, but not touching, just before the splice is made?
- The zero-speed method
