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APEX offers full-service design, engineering and manufacturing to your specifications. Our custom fasteners have enjoyed great success supplying all types and sizes of businesses in most sectors of industry.
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Hex Flange Sealing Bolts

Hex Flange Sealing Bolt - Silicone O-Ring Sealing Screw Diagram

If your equipment is exposed to high pressure, contamination, or vibration, then protect it with hex flange sealing nuts. Hex flange sealing nuts are unique because they are designed with an ingrained rubber element. The power of the sealing technology is unleashed when the nuts are torqued, causing the rubber element within them to form a vacuum-tight seal along the threading of the bolt.

All parts are made from 18-8 Stainless Steel.

O-Ring Materials Available: Silicone (-SSS), Fluorosilicone (-FSS), Buna (-BSS), and Viton (-VSS).

Apex Part NumberThreadLengthWidth Across FlatsMax Flange DiameterPart MaterialO-Ring
SE25C0025HFSEALSSS1/4"1/4"3/8".560300 Stainless SteelSilicone
SE25C0037HFSEALSSS1/4"3/8"3/8".560300 Stainless SteelSilicone
SE25C0050HFSEALSSS1/4"1/2"3/8".560300 Stainless SteelSilicone
SE25C0075HFSEALSSS1/4"3/4"3/8".560300 Stainless SteelSilicone
SE25C0100HFSEALSSS1/4"1"3/8".560300 Stainless SteelSilicone
SE31C0050HFSEALSSS5/16-181/2"1/2".680300 Stainless SteelSilicone
SE31C0062HFSEALSSS5/16-185/8"1/2".680300 Stainless SteelSilicone
SE31C0075HFSEALSSS5/16-183/4"1/2".680300 Stainless SteelSilicone
SE31C0100HFSEALSSS5/16-1811/2".680300 Stainless SteelSilicone
SE37C0050HFSEALSSS3/8-161/2"9/16".810300 Stainless SteelSilicone
SE37C0062HFSEALSSS3/8-165/8"9/16".810300 Stainless SteelSilicone
SE37C0075HFSEALSSS3/8-163/4"9/16".810300 Stainless SteelSilicone
SE37C0100HFSEALSSS3/8-161"9/16".810300 Stainless SteelSilicone
SE50C0050HFSEALSSS1/2-131/2"3/4"1.07300 Stainless SteelSilicone
SE50C0075HFSEALSSS1/2-133/4"3/4"1.07300 Stainless SteelSilicone
SE50C0100HFSEALSSS1/2-131"3/4"1.07300 Stainless SteelSilicone


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APEX FASTENERS, Inc - 15858 Business Center Drive - Irwindale, CA 91706 USA
APEX Fasteners supplies standard and custom screws, nut retainers, shoulder screws, plastites and taptites, all types of rivets, spring steel fasteners and special stampings, sems screws in standard, fractional or metric to electronics, aviation and other OEM industries worldwide. ApexFasteners.com custom manufactures screw machine components for electronic enclosure hardware as well as cold forming and cold headed specials for assembly and production requirements.
Tel: (626) 962-2219 - info@apexfasteners.com
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