Stockwell Elastomerics, Inc.

United States

Stockwell Elastomerics manufactures gaskets for submerged enclosures, usually to meet IP67 and NEMA 6 specifications. The reference depth is up to 1 meter deep which translates to roughly 16psi of omni-directional pressure. Submersion gaskets need to be well seated and require good wetting out of the gasket against the mating surfaces to fill in any tolerance stack andor surface imperfections. Any small gap or under-compressed section of the gasket will allow a continuous flow of water into the enclosure.

Solid silicone gasket products are manufactured by die cutting or waterjet cutting parts from continuous roll sheet materials or molded sheets. Solid silicone rubber offers a wide hardness range, from 10 - 70 durometer on the Shore A scale. The low durometer silicone gaskets (10A, 20A, 30A) offer excellent environmental sealing with relatively low closure force. Solid gaskets in the mid to higher durometer range require higher closure forces; these are commonly used on metal enclosures or rigid enclosures with a suitable bolt pattern to properly compress a firm gasket. Stockwell Elastomerics injection molds and compression molds solid silicone seals with custom cross-sections for improved sealing integrity for water submersion requirements.

Molded silicone seals with round or custom cross-sections are often required for heavy wash down (IP66 or NEMA 4) or water submersion requirements. Liquid silicone rubber (LSR) enables very small cross sections, down to .030", to be molded in durometers from 10 to 70 Shore A. With injection molded liquid silicone rubber, parting line flash can be reduced to ensure sealing integrity. Request our helpful Liquid Silicone Touch brochure to assist in designing enclosure seals.

Sponge silicone gasket products are soft in comparison to solid silicone gaskets, though there is some cross-over at the low durometer solids and the firm grades of silicone sponge. The firmness of silicone sponges is commonly defined by compression force deflection in a psi (pounds per square inch) range compressed 25%. 2 to 5 psi compression force deflection is considered soft, whereas 14 to 20 psi is considered firm. The closed cell structure make silicone sponge an excellent product for environmental seals such as NEMA 4 and IP64 and IP65. Silicone by nature performs well under UV and is mechanically stable over a broad temperature range, often considered for high temperature gaskets and low temperature gaskets.

Foam silicone gasket products are closely related to silicone sponge gaskets. However, they typically use platinum cure liquid silicone, and are cast onto a smooth liner giving them a smooth skin. Silicone foam products can range in cell structure from very open cell to mostly closed cell. The open cell silicone products can be used for dust seals or shockvibration gaskets. The mostly closed celled silicone foam can be used for environmental seals. Gaskets made from silicone foam would be considered to be both high temperature gaskets and low temperature gaskets due to silicone's mechanical stability in temperature extremes. Silicone is also very stable by nature under UV. BISCO silicone foams are certified by Underwriter Laboratories (UL) to have a flame rating of UL 94V-0 making them an excellent choice for electrical enclosure gaskets.

Custom dust gaskets are frequently manufactured by Stockwell Elastomerics to customer specification. Sealing out dust and other small foreign object debris (FOD) is a common gasket applications for Stockwell Elastomerics' customers. Dust sealing is usually less rigorous than water sealing, allowing for a wider range of materials. But proper material selection is still critical for proper gasket performance. Common specifications for dust sealing are NEMA Type 1, IP5X and IP6X (IP50 and IP60 have no water sealing requirements).

Stockwell Elastomerics has a unique capability to manufacture large gaskets from silicone materials. In-house waterjets, stock roll materials, custom continuous feed UV curing oven and designated assembly cell allows Stockwell Elastomerics to manufacture very large, one-off gaskets with minimal setup cost. Most very large gaskets are assembled with bonded dovetail joints, joints allow for optimizing sheet yield and cost.

Stockwell Elastomerics manufactures custom silicone gaskets from silicone in its various forms, including solid silicone, expanded silicone sponge and silicone foam. Stockwell Elastomerics also injection molds platinum cured liquid silicone parts and gaskets, and compression molds specialty gaskets from electrically conductive silicone and chemical resistant fluorosilicone.