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Universal high-pressure gasket material

KLINGERSIL® C-4300 is a universal high-pressure gasket material that is resistant to hot water, steam, oil, hydrocarbons and many other chemicals which makes it suitable for many different media.

This compressed fiber gasket material is manufactured with aramid fiber reinforced with a nitrile binder.
Klingersil C-4300

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

Creep relaxation ASTM F38B (1/32") 25 %
Sealability ASTM F37A (1/32") < 0.25 ml/hr
Gas Permeability DIN 3535/6 < 0.5 ml/min
Compressibility ASTM F36J 7 - 17 %
Recovery ASTM F36J 50 % minimum
KLINGER Hot Compression Test
Thickness Decrease 73°F (23°C)
Thickness Decrease 572°F (23°C)

15 % initial
25 % additional
Weight increase ASTM F146 after immersion in
Fuel B, 5h/73°F (23°C)

10 % maximum
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 - 5 %
0 - 5 %
0 - 5 %
0 - 10 %
Dielectric Strength ASTM D149-95a 18 kV/mm
Density ASTM F1315 100 lb/ft ³ (1.6 g/cc ³)
Leachable Chloride Content FSA Method 200 ppm
ASTM F104 Line Call Out F712121B3E11K6M4
Color Black or white

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-4300 Liquid
C-4300 Gasses and Steam
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.