High-temperature seals have two main purposes; to provide a secure barrier to prevent any gases, liquids, or other matter from entering or exiting the sealed structure, and to ensure that the structure can withstand high temperatures and any pressure without breaking.

A successful high-temperature seal will ensure that the structure has a longer lifetime with less unplanned downtime, ultimately saving the company money and time.

These seals are used in a wide range of industries, including oil and gas, aerospace, hearth, and automotive. Mid-Mountain Materials, Inc. supply a large selection of high-temperature seals for these industries.



Our THERMOPAK® range is designed for use in high-temperature applications as thermal insulation barriers. They also find use in applications where there is a risk of chemical attack or abrasion.

Tadpole Gaskets

THERMOPAK® Tadpole Gaskets are specifically developed for applications that may have unusually shaped components and require a high-temperature seal with maximum flexibility. These gaskets are composed from a range of core and cover materials, including stainless steel mesh, fiberglass textiles, refractory ceramic fiber textiles, and coated fabrics.

Tadpole Gaskets can be used as seals in non-ferrous metals operations, furnace and oven doors, gas fireplaces, and for fume and emissions control.

Die Cut Gaskets

Our range of THERMOPAK® Die-Cut Gaskets are custom made to our client’s specifications, and they are used to fill any imperfections on surfaces that require a high-temperature seal. They are made from materials that provide the highest level of chemical, abrasion, and heat resistance, making them a popular choice in many industries.

We are able to manufacture these die cut gaskets with a range of insulation materials, including refractory coated fabric, ceramic fiber paper, fiberglass paper, and silicone coated fabrics.


The THERMOSEAL® family of products is designed for use as high-temperature seals in thermal insulation and high-temperature adhesive applications. All of the products are manufactured to prevent thermal expansion and contraction, ensuring the seals remain secure.

Refractory Cements, Moldables, and Coatings

THERMOSEAL® Refractory Cements, Moldables, and Coatings are all developed from bulk refractory fibers. Depending on the application they can be formed into shapes and linings, or pushed into cracks or holes to provide a seal and protect against erosion.

These products have extremely low shrinkage, high strength, and excellent insulation properties. The typical applications of these products include coatings for furnace linings, troughs, molds, and burners, induction furnace coil coating, molten aluminum splash protection, and lightweight refractory coatings.


Our range of ARMATEX® Coated Fabrics provides superior heat protection, making them perfect for use as high-temperature seals. These fabrics also display outstanding durability when exposed to chemicals and abrasion.

Refractory Coated Fabrics and Textiles

These fabrics and textiles are very effective as high-temperature seals due to the use of Mid-Mountain’s proprietary refractory coating, Q-Mix. Q-Mix can be applied to a range of substrates, and it is used to increase temperature, chemical, and abrasion resistance of the substrate.

This range also includes fabrics and textiles coated with various polymer coatings that provide outstanding thermal insulation properties, allowing them to be used in fabricated components for specialty seals.

These high-temperature seals have applications in the aerospace, automotive, and insulation and aluminum industries.

High-Temperature Seals from Mid Mountain

Mid-Mountain have a large range of products designed for use as high-temperature seals. We can also provide custom solutions where required. If you would like any more information about high-temperature seals, please contact us.