AK Flex Insulation

This semi-rigid fiberglass blanket measures 48" (1,219 mm), has a density of 2.5 PCF (40 kg/m³), and comes in roll form. The fiber orientation provides excellent compressive strength while maintaining flexibility for ease of installation. 

AK Flex with ECOSE® Technology coming 2025.

Applications

Certifications
Product Features
For Pipes & Tanks
Typical uses include tanks, vessels and large-diameter (greater than 10" (25.4 cm)) pipes. It can be used for any curved or irregular surfaces that require finished characteristics of rigid fiberglass insulation.
Versatile
AK Flex is available plain or with a factory applied ASJ or FSK vapor retarder jacket.
Sustainable
All of our products are made from sustainable resources, such as recycled glass and sand.
Product Details
Technical Data
 
 
TECHNICAL DATA
PROPERTY (UNIT) TEST PERFORMANCE
Corrosiveness ASTM C665 Does not accelerate corrosion of steel
Maximum Service Temperature ASTM C411 850° F (454° C)
Linear Shrinkage ASTM C356 Less than 0.3%
Water Vapor Sorption (by weight) ASTM C1104 5% or less
Water Vapor Permeance ASTM E96, Procedure A 0.02 perms (FSK, ASJ facing
Puncture Resistance TAPPI Test T803, Beach Units FSK facing: 25, ASJ facing: 50
Compressive Strength ASTM C165 Not less than 25 PSF (1.2 kPa) at 10% deformation
Mold Growth ASTM C1338 Pass
Surface Burning Characteristics
(flame spread/smoke developed)
ASTM E84, UL 723, CAN/ULC S102 UL/ULC Classified FHC 25/50

 
Thermal Conductivity k
 
MEAN TEMPERATURE K K(SI)
75° F (24° C) 0.24 0.035
100° F (38° C) 0.25 0.036
200° F (93° C) 0.32 0.046
300° F (149° C) 0.39 0.056
400° F (204° C) 0.49 0.070
500° F (260° C) 0.61 0.088
Forms Available
FORMS AVAILABLE
THICKNESS WIDTH LENGTH
1" (25 mm) 48" (1,219 mm) 52' (15.85 m)
1½" (38 mm) 30' (9.14 m)
2" (51 mm) 26' (7.92 m)
2½" (64 mm) 21' (6.40 m)
3" (76 mm) 18' (5.48 m)
4" (102 mm 10' (3.05 m)
Stretch-outs
STRETCH-OUTS | ADDITIONAL 2" (51 mm) TO 4" (102 mm) SHOULD BE ADDED FOR LAP

NOMINAL
IRON PIPE
SIZE

IRON PIPE
OUTSIDE
DIAMETER
THICKNESS
1" (25 mm) 11/2" (38 mm) 2" (51 mm) 3" (76 mm)
10" (254 mm) 103/4" (273 mm) 401 ⁄8" (1019 mm) 431/4" (1099 mm) 463/8" (1178 mm) 525/8" (1337 mm)
12" (305 mm) 123/4" (324 mm) 463 ⁄8" (1178 mm) 491/2" (1257 mm) 523/4" (1340 mm 59" (1499 mm)
14" (356 mm) 14" (356 mm) 503 ⁄8" (1280 mm) 531/2" (1359 mm) 565/8" (1438 mm) 627/8" (1597 mm
16" (406 mm) 16" (406 mm) 565 ⁄8" (1438 mm) 593/4" (1518 mm) 627/8" (1597 mm) 691/8" (1756 mm
18" (457 mm) 18" (457 mm) 627 ⁄8" (1597 mm) 66" (1676 mm) 691/4" (1756 mm 751/2" (1918 mm)
20" (508 mm) 20" (508 mm) 691 ⁄8" (1756 mm) 723/8" (1838 mm) 751/2" (1918 mm) 813/4" (2076 mm)
22" (559 mm) 22" (559 mm) 751/2" (1918 mm) 785/8" (1997 mm) 813/4" (2076 mm) 88" (2235 mm)
24" (610 mm 24" (610 mm 813/4" (2076 mm) 847/8" (2156 mm) 88" (2235 mm) 943/8" (2397 mm)
26" (660 mm) 26" (660 mm) 88" (2235 mm) 911/8" (2315 mm) 943/8" (2397 mm) 1005/8" (2556 mm)
28" (711 mm) 28" (711 mm) 943 ⁄8" (2397 mm) 971/2" (2477 mm) 1005/8" (2556 mm) 1067/8" (2715 mm)
30" (762 mm) 30" (762 mm) 1005 ⁄8" (2556 mm) 1033/4" (2635 mm) 1067/8" (2715 mm 1131/8" (2873 mm
32" (813 mm) 32" (813 mm) 1067 ⁄8" (2715 mm) 110" (2794 mm) 1131/8" (2873 mm) 1191/2" (3035 mm)
34" (864 mm) 34" (864 mm) 1131 ⁄8" (2873 mm) 1161/4" (2953 mm) 1191/2" (3035 mm) 1253/4" (3194 mm)
36" (914 mm) 36" (914 mm) 1191/2" (3035 mm 1225/8" (3115 mm) 1253/4" (3194 mm) 132" (3353 mm)
38" (965 mm) 38" (965 mm) 1253/4" (3194 mm) 1287/8" (3273 mm) 132" (3353 mm) 1381/4" (3512 mm)
40" (1016 mm) 40" (1016 mm 132" (3353 mm) 1351/8" (3432 mm) 1381/4" (3512 mm) 1445/8" (3673 mm
42" (1067 mm) 42" (1067 mm) 1381/4" (3512 mm) 1411/2" (3594 mm) 1445/8" (3673 mm) 1507/8" (3832 mm)

 
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