Pkg Solutions
Quality Glossary
Corrugated Flutes
Official definitions of the different corrugated flute types
can vary, the ones below are from BS 1133 section 7.5.
Details of Flute Forms - Metric
|
Flute Form
|
Approx. Corrugations per Meter
|
Approx. Height of Corrugations
|
Typical Draw Factors
|
A Flute
|
105 to 125
|
4.5 to 4.7 mm
|
1.55 +/- 5%
|
B Flute
|
150 to 185
|
2.1 to 2.9 mm
|
1.33 +/- 5%
|
C Flute
|
120 to 145
|
3.5 to 3.7 mm
|
1.44 +/- 5%
|
E Flute
|
290 to 320
|
1.1 to 1.2 mm
|
1.27 +/- 5%
|
The caliper of the liners and fluting medium used for a
particular board, would be added to the flute height to give the
overall board caliper. Below are the measurements in Imperial units.
Details of Flute Forms - Imperial
|
Flute Form
|
Approx. Corrugations per Yard
|
Approx. Height of Corrugations
|
Typical Draw Factors
|
A Flute
|
96 to 114
|
0.1772 to 0.185"
|
1.55 +/- 5%
|
B Flute
|
137 to 169
|
0.0827 to 0.1142"
|
1.33 +/- 5%
|
C Flute
|
110 to 133
|
0.1378 to 0.1457"
|
1.44 +/- 5%
|
E Flute
|
265 to 293
|
0.0433 to 0.0472"
|
1.27 +/- 5%
|
The measurements used in design allowance calculations are
usually standardized and rounded. The table below shows the general
values usually used for design allowances.
Flute
|
Millimeters
|
Inches
|
Inches
|
A
|
6
|
0.25
|
1/4
|
B
|
3
|
0.125
|
1/8
|
C
|
5
|
0.1875
|
3/16
|
E
|
2
|
0.0625
|
1/16
|
F
|
1
|
0.04688
|
3/64
|
G
|
0.7
|
0.03125
|
1/32
|
N
|
0.5
|
0.01563
|
1/64
|
EB
|
5
|
0.1875
|
3/16
|
BC
|
8
|
0.3125
|
5/16
|
CA
|
11
|
0.4375
|
7/16
|
AB
|
9
|
0.375
|
3/8
|
AAC
|
14
|
0.5625
|
9/16
|
AAA
|
16
|
0.625
|
5/8
|