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Chemically resistant sheet also has excellent dielectric strength

KLINGERSIL® C-7400 satisfies both sealing and electrical requirements. C-7400 is resistant to moderate caustics and acids which makes it suitable for paper mills. It can also act as an insulator or barrier to the flow of electrons from one flange to another due to its high dielectric strength.

This material is manufactured with synthetic fiber reinforced with an EPDM binder.


Typical Values Refer to 1/16" Thick Material Unless Noted

Creep relaxation ASTM F38B (1/32") < 25 %
Sealability ASTM F37A (1/32") < 0.5 ml/hr
Gas Permeability DIN 3535/6 < 1.0 ml/min
Compressibility ASTM F36J 7 - 17 %
Recovery ASTM F36J > 45 %
KLINGER Hot Compression Test
Thickness Decrease 73°F (23°C)
Thickness Decrease 572°F (300°C)
tested at 3625 psi gasket stress
15 % initial
17 % additional
Weight increase ASTM F146 after immersion in
Fuel B, 5h/73°F (23°C)

< 20 %
Thickness Increase ASTM F146 after immersion in
ASTM Oil IRM 901, 5h/300°F (149°C)
ASTM Oil IRM 903, 5h/300°F (149°C)
ASTM Fuel A, 5h/73°F (23°C)
ASTM Fuel B, 5h/73°F (23°C)

0 - 20 %
15 - 30 %
0 - 20 %
5 - 20 %
Dielectric Strength ASTM D149-95a 22 kV/mm
Density ASTM F1315 94 lb/ft ³ (1.5 g/cc ³)
Leachable Chloride Content FSA Method 200 ppm
ASTM F104 Line Call Out F712441B4E34K6M4
Color White/Gray


The pressure/temperature graphs shown are the most current method of determining the suitability of a gasket material in a known environment. However, chemical compatibility must also be considered.
pT diagram for thickness 1/16":
C-7400 Liquid
C-7400 Gases and Liquids
In area 1 the gasket material is suitable using common installment practices subject to chemical compatibility

In area 2 appropriate measures are necessary for installation of the gasket to ensure maximum performance. Please call or refer to KLINGERexpert for assistance.

In area 3 do not install gaskets in these applications without first referring to KLINGERexpert or contacting KLINGER Thermoseal's technical support service.
The ability of a gasket to make and maintain a seal depends not only on the style and quality of the gasket material, but also on medium being sealed, the flange design, the amount of pressure applied to the gasket by the bolts and how the gasket is assembled onto the flanges and tightened. These factors are beyond the manufacturer's control. Please take note of our installation manual in TECHNICAL RESOURCES.