CN sản xuất giấy carton sóng

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giấy carton sóng
Chương 11


Corrugated board
1.

Construction : linerboard and medium
Material :heavy paper ---containerboard
Facings---kraft linerboard
Medium---one-ply sheet, hardwood or recycled fiber
Linerboard
(flat facing)

Medium
(fluted wavy)


2. Four types combined board
a. Single Face
one medium
one liner board
(for protective wrapping)

b. Single Wall
(Double Face)
one mediu
two liner boards

二
c. Double Wall
two mediums
three liner boards

d. Triple Wall
three mediums
four liner boards

Direction: Machine Direction
Cross Direction ----flute direction


3. Flute
Profile: arches with proper curve---- the strongest way to span space
Flutes as arches--- resist bending and pressure, support weight, as cushion.
Proper curve: between U and V (Also has its advantages)
Flutes also as a insulator to protect sudden temperature changes
Vertical linerboard provides strength; protects from damage.
Several standard shapes
(A,B,C,E,F…) ,
Contrast:
A-flute ---- the largest profile
B-flute ----smaller than A
C-flute ----between A and B
E-flute ---- smaller than B
F-flute ---- micro-flute
New flute---Macro-flute

Combined board ---Different flute profiles combined in one board
one layer of medium might be A-flute while the other C-flute
Manipulate the compression and cushioning strength, total thickness of the board.
Standard flute configurations
Flute

Flutes/ m

Flutes/ ft

Thickness
*

Factor

A

100~120

30~36

4.67 mm

1.54

B

145~165

44~50

2.46 mm

1.32

C

120~140

36~42

3.63 mm

1.42

E

280~310

86~94

1.19 mm

1.27

*Not including facings;
1foot = 0.3047999m
“Take-up factor” is the
length of medium per
length of finished

corrugated board

Described: the component of grammage or basis weight, from outside to inside
eg. corrugated board “205/127C/161”----Outside liner = 205grams;
Medium = 127 grams, formed to C-flute;
Inside liner = 161grams


4 . Fiberboard Grades : Weight ; Thickness ; Material

Grammage: the mass in
grams per square meter.
Basis weight: the weight
in pounds per 1,000
square feet ( abbreviated
lb/MSF).

The most commonly used
corrugating medium weights
Grammage/g

Basis Weight/b

127

26

147

30

161

33

195

40

Material :
Linerboard --- natural kraft ;Solid bleached white kraft ; Mottled white ; oyserboard
Linerboard with a whiter surface provide better graphics.
 Recycled or secondary fiber ---producing both two components
Recycled board ---smoother surface finish; low Coefficient of Friction; excellent printing
surface.



The most commonly used linerboard grades, based on Mullen burst test grading.

1 kg = 2.2046 b
1 meter = 3.28084 foot
1 g/m2 = 0.205 b/MSF

North American Grades
Grammage
Basis Weight
127g
26b
161g

33b
186g
38b
205g
42b
----337g
69b
Other grades
---

--

European Grades
Grammage
125g
150g
-200g
225g
250g
300g
400g
440g

A generation of newer linerboards has high-performance boards, meeting ECT
(Edgewise Compressive strength) rather than Mullen burst test and basis weight
requirements.
Lighter grades of the high-performance boards to get satisfactory performance


5. Corrugating Adhesive

The corrugating machine forms the medium into a fluted pattern and bonds it to the
linerboard facings , usually with a starch-based adhesive
1) A starch-based adhesive applied at about 10 to 14 grams per square meter.
2) Requirements : not tolerant high moisture and loses strength quickly.
3) When higher resistance is needed, starches can be modified or supplemented by
the addition of various polymeric materials.
4) Weather-resistant adhesive would maintain box properties at a somewhat higher
level for a longer period.
5) Water-resistant adhesive would be required for those applications where the
finished container will be in actual contact with water for periods of time, and the
coating or waxed should be treated


6. Broad Manufacture
Corrugating machine is made up of a set of stations that take the appropriate
linerboards and mediums, shape the flutes, join fluted medium to linerboards.

Precondition
medium with heat
and steam



Pretreated
linerboards to the
same temperature
and moisture
Brass fingers
Flute tips adhesive
The single-facer of a corrugating machine is where the flutes are formed

and bonded to the inside liner


Bridge ---Draped in an overlapping wave pattern to the double-backer station
Purpose---Isolating the two ends of the corrugating machine; balance; slow down

The double-backer section of corrugating machine where a second linerboard
is applied to the single-faced material coming from the single-facer unit


Manufacture:
•
•
•
•
•
•
•

Adhesive --- On the other side of the medium to glue outer linerboard.
Final heating and cooling section --- Between two long , flat belts.
Trimming edges--- Slit board to required width and length and stack
Balanced construction--- Outer and inner have identical grammage.
Upgrading only one liner may gain performance.
Unbalanced constructions --- more problems with board wrappage.
Heavier liner is placed on the outside for better printing and on the inside
for better compression strength.


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