No_6_1959 — Page 20

JH

ANKARBOARD

ACOUSTIC BOARD

1/2′′ or 3/4′′ porous perforated Ankarboard in widths of 300 mm, 400 mm, 12′′ and 16" and in lengths up to about 16' as shown below.

300 mm and 12" widths

with longitudinal ship-lap and

groove

Lengths

2266 mm abt. 7′ 5′′ 3112 mm 10' 2' 3676 mm 12′′ ′′ 4240 mm 13' 11* 4804 mm IS′ 9′′

with ship-lap and groove also at the ends

Lengths

602 mm abt. 2' 1166 mm 3′ 10′′ 1730 mm 5' 8" 2294 mm 7′ 6′′

400 mm and 16′′ widths

with longitudinal ship-lap and groove

Lengths

2337 mm abt, 7′ 8′′ 3111 mm 10" 5" 3885 mm 12′ 9′′ 4272 mm 14′′ 5046 mm 16′ 61⁄2"

When the boards are fixed, they over- lap each other by 5 mm (approx. 3/16”). The grooves cut along the sides allow the perforated sheets to form decorative geometrical patterns. By virtue of their length these boards are very easily fixed, and when in position provide an ex- tremely attractive surface.

Packed 8 sheets to the crate.

* X

120

110

100

90

80

70

60

50

40

30

20

10

with ship-lap and groove also at the ends

Lengths

817 mm abt. 2′ 8′′ 1204 mm 3′ 111⁄21⁄2" 1591 mm 5'2′′ 1978 mm 6′ 6′′ 2365 mm 7*9*

"FA" quality-unpainted "FAM" quality supplied treated with a white

washable paint,

OH YES

NOISELESS

Sound absorption coefficient

for perforated acoustical tile

of wood fibre as shown in figure.

Measurements after

the reverberation time method. Absorption coefficient calculated after the Norris-Eyring formula

T= 0,161

•

– S log (1-x)

Volume of test room 86 m

Sample area 5,76 mi

2

J

The tiles mounted on 1′′ laths

Size of tiles 30 × 30 em 20 × 20 holes.

40

B 100 H:

2

3

4 5.

$ 1000 Hz 2

Frequency

3

4 5

8 10 kH2

SVENSKA

CELLULOSA AKTIEBOLAGET

SUNDSVALL · SWEDEN

THE HONG KONG & FAR EAST BUILDER

VOLUME 14, NUMBER 6

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