Tadpole gaskets are unique thermal sealing solutions comprised of a heat-resistant cover and a durable core material arranged in a distinctive bulb and tail structure. The external material, typically thermally-resistant,  is wrapped around the core material to form a cylindrical bulb. The edges of the tape or fabric are then fused together to form the characteristic tail which fits to the edges or joints of components such as fireplace windows.

This tightly-sealed, cylindrical configuration is primarily designed to insulate firing or heating components such as furnace doors and expansion joints. Tadpole gasket cover materials must therefore exhibit outstanding thermal resistance for temperatures of up to 5000°F (2760°C), with considerations for additionally-corrosive or abrasive process conditions. Mechanical abrasion from metallic mating surfaces, moisture-related degradation, and chemical corrosion must all be considered for application-specific tadpole gaskets.

Tadpole Gasket

This article will explore the purpose and capacities of tadpole gaskets in more detail:

Tadpole Gasket Materials

Tadpole gasket tapes are typically manufactured using stainless steel mesh, silica or fiberglass fabrics as a base material, with a refractory or silicone coating to optimize the materials’ heat-resistant properties.

Mid-Mountain Materials, Inc. has constructed tadpole gaskets using mechanically-stable HYTEX® 1000 tape or fabric, which is comprised of high-purity E glass yarns. This may be coated with a proprietary ARMATEX® coating, to enable continuous use temperatures of up to 1000°F and comprehensive prevention of CO2 emissions in firing applications. The dimensions of the seal’s distinctive shape can be tailored to specific requirements, ensuring optimal sealant performance. This high-performance tape encapsulates a core of fiberglass rope, stainless steel, or silicone rubber extrusions, depending upon the density requirements of the sealing application.

Our THERMOPAK® Tadpole Gasket insulation can be customized to distinct application requirements, including ductwork and boiler sealing. The unique material combinations available provide application-specific resistances to steam and thermal expansion, with varying levels of formability for ease of integration into component joints and seams.

Tadpole Gasket from Mid-Mountain Materials

Mid-Mountain Materials, Inc. specializes in high-performance thermal insulation products for the most demanding applications. Our range of products includes textiles, coated fabrics, moldables and fabricated thermal barriers with outstanding mechanical stabilities under extreme conditions. We have been manufacturing tadpole gaskets and high-strength thermal seals since 1976, optimizing the capabilities of our thermally-stable HYTEX® fabrics and THERMOPAK® tadpole gaskets for high-temperature sealing applications.

If you would like any more information about our tadpole gaskets, please do not hesitate to contact us.