Types of EMI/RFI Connector Gaskets
Subminiature D-Gasket
These gaskets are the conventional type you would see in the back of a computer. These rectangular connectors are normally made out of a EMI gasketing material for both EMI and environmental protection. The standard thickness on these gaskets is .032’’ in thickness. The shell sizes range from 9 to 50 pin. For example, NEDC manufactures D-Subminiature Connector gaskets for MIL-DTL-83513 (M83513 connector gaskets), and MIL-DTL-24308 (M24308 connector gaskets). These sub-micro, and d-subminature connector gaskets are a standard manufactured connector gasket for NEDC.
EMI/RFI Mounting Flange Connector Gaskets for Military Grade Connectors
These gaskets are available from the slash sheet MIL-DTL-83528/4. They are usually circular in shape in the middle with radii on the corners. They can either be slotted or with holes. The M83528/4 is strictly circle diameter screw holes. The standard thickness on these gaskets is .032’’ in thickness. NEDC commonly deals with the flange gaskets that meet connectors MIL-DTL-2600, MIL-DTL-83723, and MIL-DTL-38999 (M38999 gaskets). These connector gaskets that NEDC supplies are mostly on wall mounting receptacles for a number of military grade connectors.
We thought it would be useful to make a table of different M83528/4 that NEDC traditionally either has in stock or can turn very quickly. The reason for this is these gaskets are so commonly used that any die-cutting manufacturer typically has stock of the steel-rule dies that are required to make these parts.
Breakdown of M83528 numbers for Military Grade EMI/RFI Gaskets
M83528/LLLXDDD
M83528=MIL-DTL-83528 (the overall specification)
LLL=Slash Sheet(in this slash sheet indicating connector gaskets)
X=Material Type, (Several Material Types Available, Type B, and Type D most popular)
DDD=The size (34 sizes available)
Fast-Turn/Standard Connector Gasket Pin #s
Electrically Conductive EMI Gasketing Materials
There are many different types of EMI gasketing materials available for use. One of the more common materials NEDC sees is silver/aluminum filler with either fluorosilicone or silicone rubber. These materials are called out in the MIL-DTL-83528 as Type B and Type D. They are the most commonly used gasketing materials for the M83528/004 pin number.
Type D has shielding effectiveness of 90 dB @ 10 GHz. Type D is a Fluorosilicone Rubber material filled with either passivated or non-passivated silver/aluminum particles.
Type B has shielding effectiveness of 100 dB @ 10 GHz. Type B is a Silicone Rubber material filled with silver aluminum particles.
However, the MIL-DTL-83528 provides other different types of materials including Type A, Type C, Type E, Type F, Type J, Type K, Type L, and Type M.
Non-Conductive Gasketing Materials for Connector Gaskets
-Silicone Rubber per ZZR765 Class 2A2B, A-A-59588 2A/2B
-Fluorosilicone Rubber per MIL-R-25988 Type II, Class 1, Various Grades
More Information on Military Grade Connector Gaskets
For more information on EMI connector gaskets please contact sales@nedc.com. NEDC uses waterjet cutting and die cutting to convert gasketing materials into connector gaskets.