US Patent 6862852 Sealing system and gasket therefor

The invention releases to a sealing system comprising a cylindrical tube of a material that is capable of deformation under the influence of a temperature increase, and a gasket of an at least partially elastic material for sealingly retaining the tube in a lead-through housing coaxial with the tube by forming a collar therearound, wherein said gasket is made of a fire-retardant material with a base of a cross-linkable material and an expandable material, in such an amount and of such a composition that a temperature increase above the plasticizing point of the tube will cause the gasket to expand to such an extent that the tube is compressed and a medium-tight seal of the lead-through housing and the tube is obtained.