Padding cardboard is intended for the manufacture of sealing gaskets in flange, coupling and other connections, where the use of other materials is impossible. In accordance with GOST 9347-74, the following types are distinguished: grade A - cardboard for gaskets of compounds used in the environmentoils,gasoline, water; brand B - cardboard for joint gaskets used in air and water environments.
Brand "A". Oil and gasoline resistant. It is intended for the manufacture of gaskets that ensure tightness between flat metal surfaces in the following environments:gasoline up to 90 °C, oil up to 120 °C, water up to 110 °C. It is produced in letters.
It is produced: in sheets - thickness 0.9 - 3.0 mm.(//tractor-service.com)
This material is used for sealing joints and connections of the "smooth", "spike-groove", "protrusion-slot" type in vessels, devices, pumps, fittings, pipelines, compressors and other units with various types of connections.