EMI Waveguide Gaskets: Standard and Custom

SSP makes standard EMI waveguide gaskets in M83528 and EIA sizes from the electrically conductive silicones we make right here in the USA. 

We also fabricate custom EMI waveguide gaskets for both non-military and application-specification challenges.

Compare our waveguide gasket materials to Parker Chomerics CHO-SEAL and Nolato Jabar.

Get quick lead times, low minimum order quantities, and a Certification of Analysis with every batch. 

EMI Waveguide Gaskets: MIL-DTL-83528 & Flange Seals

Specialty Silicone Products (SSP) manufactures high-performance EMI waveguide gaskets engineered to eliminate microwave and radio frequency (RF) energy leakage across waveguide flange interfaces. Designed for radar systems, satellite communications (SATCOM), aerospace electronics, and military defense networks, our waveguide gaskets provide dual performance: continuous electromagnetic attenuation and hermetic environmental sealing.

Manufactured in Ballston Spa, New York, at our ISO 9001:2015 and AS9100D certified facility, SSP’s EMI waveguide gaskets are cut or molded from conductive silicones and fluorosilicones. We offer standard WR-series dimensions, official MIL-DTL-83528/013 slash sheet specs, and custom geometries with low minimum order quantities (MOQs).

Supported Waveguide Sizes & Flange Specifications

SSP produces EMI waveguide gaskets for standard rectangular and circular Electronic Industries Alliance (EIA) Waveguide (WR) sizes:

Waveguide SizeFrequency Range (GHz)Flange Style / TypeCommon MIL-DTL-83528 Slash Specs
WR-28 to WR-4218.0 – 40.0 GHzMillimeter Wave / Ka-Band FlangesM83528/013 (Custom Die-Cut)
WR-62 to WR-908.2 – 18.0 GHzKu-Band / X-Band Radar FlangesM83528/013-001 to -010
WR-112 to WR-1873.95 – 10.0 GHzC-Band / X-Band SATCOM FlangesM83528/013-011 to -020
WR-284 to WR-6501.12 – 3.95 GHzS-Band / L-Band High-Power RadarM83528/013 Large Format

Conductive Elastomer Material Selection

Waveguide flanges demand precise volume resistivity and low contact resistance to prevent RF arcing and power loss across the joint.

  • SSP2529 (Nickel-Plated Aluminum / Silicone): QPL-listed under MIL-DTL-83528 Type B. Delivers >100 dB shielding effectiveness with lightweight galvanic compatibility for aluminum waveguide flanges.

  • SSP2486-70 (Silver-Plated Aluminum / Fluorosilicone): QPL-listed under MIL-DTL-83528 Type D. Engineered specifically for airborne radar and naval waveguide systems exposed to jet fuel, hydraulic fluids, and harsh solvents.

  • SSP2569-65 (Silver-Plated Copper / Silicone): QPL-listed under MIL-DTL-83528 Type A. Designed for high-power RF systems requiring maximum conductivity and attenuation (>110 db)

  • SSP502 Series (Nickel-Graphite / Silicone): Premium commercial-grade conductive elastomer providing high shielding attenuation (80to 100 dB) and superior resistance to galvanic corrosion at a lower material cost.

Precision Waveguide Compression Dynamics

EMI waveguide gaskets
  • RF Power Leakage Prevention: High-frequency microwave energy traveling through a waveguide can escape through tiny gaps in mating flanges. SSP’s EMI waveguide gaskets maintain continuous contact across the flange face, eliminating RF arcing and insertion loss.

  • Environmental & Pressure Sealing: Prevents moisture, dust, and atmospheric pressure loss in pressurized waveguide feeds.

  • Die-Cut & Molded Precision: Available with raised sealing beads, alignment bolt holes, or custom inner aperture dimensions to preserve impedance matching.

Frequently Asked Questions (FAQ)

What is the primary purpose of an EMI waveguide gasket?

An EMI waveguide gasket seals the mating junction between two waveguide flanges. It provides continuous electrical conductivity to block high-frequency microwave/RF energy leakage while simultaneously establishing an environmental seal against moisture and atmospheric pressure loss.

Are SSP’s waveguide gaskets QPL certified under MIL-DTL-83528?

Yes. SSP manufactures QPL-listed conductive silicone and fluorosilicone materials compliant with MIL-DTL-83528 specifications, including slash sheet M83528/013 for waveguide flange seals.

Can SSP manufacture custom or non-standard waveguide gaskets?

Yes. In addition to standard EIA WR-series sizes, SSP die-cuts and flash-cuts custom waveguide flange gaskets directly from customer CAD files or technical drawings.