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Let’s meet up at the Navy League Show – Sea, Air and Space Expo April 3-5, 2017

We are looking forward to attending the forthcoming Sea-Air-Space expo in early April where, the organisers tell us, there will be over 200 exciting and interactive exhibits showcasing the latest in maritime, defense and energy technology.

As you will know, Sea-Air-Space is the largest maritime exposition in the U.S. and continues as an invaluable extension of the Navy League’s mission of maritime policy education and sea service support. Sea-Air-Space continues to support the mission of the Navy League and lead the way as “THE” Exposition to attend each year to display the most current information and technology relevant to maritime policy.

We’re keen to see what’s new and, of course, to catch up with colleagues in the industry. If you plan to be there and would like to meet up, please get in touch and we’ll get a date in the diary.

System Level Gasket Considerations for RFI Susceptibility

RFI (Radio Frequency Interference), also known as EMI (Electromagnetic Interference), interrupts or interferes with the operation of electronic components, and electrical circuits. RFI or EMI may be introduced intentionally as in the case of electronic warfare, or unintentionally from an electronic or electrical device.

There are essentially two basic approaches for reducing or shielding electromagnetic emissions from a device or system. The first is shielding at the printed circuit board level utilizing proper design techniques. The second is to place the device or system in a shielded enclosure. This article will address shielding at the system level through use of a gasket.

Gaskets are used to maintain shielding effectiveness through proper seam treatment. It is, in fact, the unshielded seams that account for most of the RFI leakages in an enclosure. Of course, the shielding effectiveness of a seam is dependent upon the materials, contact pressure, and surface area. The solution to radiated problems in an enclosure is to make all the joints or seams of adjoining metal pieces continuous. If the adjoining metal pieces lack continuity, a radiating aperture for RF currents is created. Gaskets maintain conductive contact across the mating surfaces. The solution to radiated problems is, indeed, the gasket.

The majority of gasket applications involve two types of forces: compression and shear. When gaskets are installed under a flat cover panel in a compression configuration, the pressure preserves the shielding effectiveness of the seam. The alternative is a shear application wherein a flange or channel arrangement is maintained to preserve the shielding effectiveness.

Regardless of gasket type, there are several important factors that must be considered during the selection process. In addition to shielding effectiveness, one must take into account Radio Frequency (RF) impedance, material compatibility, gasket height, compression force, compressibility, and corrosion control.

The height or diameter of the gasket compensates for the joint unevenness of the mating surfaces, so that enough force can be applied, resulting in compressibility. Moreover, the difference between the minimum and maximum compressed gasket height should equal the joint unevenness.

Compression force– the force required to achieve maximum shielding effectiveness—is also essential, since the higher the pressure or compression force, the lower the impedance. A minimum closure force is recommended to obtain low surface contact resistivity and good shielding. Thus, a good joint seal needs to be a low surface contact resistivity, as well as a low gasket resistivity.

Corrosion is also a concern because it leads to the gasket material becoming insulative. This, in turn, reduces shielding effectiveness. Notably, there are two types of corrosion. The most common is galvanic corrosion due to contact between two dissimilar metals in the presence of moisture. The second type is electrolytic, and is due to current flow between two metals in the presence of an electrolyte.

In our next newsletter, we will address the various gasket materials available, as well as the cost considerations in good gasket design.

Fabritech, Inc. Ships Custom EMI Gaskets to a Leading Defense Contractor for a USV (Unmanned Surface Vehicle)

West Chester, Pennsylvania – Fabritech, Inc., part of the Integrated Polymers Group, a manufacturer of precision engineered custom EMI, RFI and Thermal Gaskets, recently shipped an order of custom EMI gaskets to a leading defense contractor. These gaskets will be integrated into a USV (Unmanned Surface Vehicle).

The gasket material chosen for this project is a fluorosilicone polymer with silver plated aluminum particle fill for low electrical resistance, excellent shielding and grounding properties. This material is widely used for defense and aerospace EMI applications, where high conductivity and chemical resistance is needed.

“Our company is proud to be part of this important military defense program,” said Fran Berardinis, Operations Manager. “Our custom EMI gasket solutions have been extremely reliable for our military customers.”

Fabritech, Inc. is a high technology, high capability company committed to exceeding client expectations; our expertise encompasses the entire range of Aerospace and Defense, including applications for Land, Sea and Space.

Our products include seals, gaskets and O-Rings manufactured from MIL-STD-83528 approved materials, including: thermally conductive elastomers, oriented wire in silicon, woven mesh, wire mesh, and microwave absorbing materials.

Fabritech, Inc. Ships Custom Thermal Gap Gaskets to a Leading Defense Contractor for Tactical Software-Defined Radios (TSDR)

West Chester, Pennsylvania – Fabritech, Inc., part of the Integrated Polymers Group, a manufacturer of precision engineered custom EMI, RFI and Thermal Gaskets, recently shipped an order of custom Thermal Gap gaskets to be integrated into Tactical Software-Defined Radios for a leading defense contractor.

The gasket material chosen for this project is a thermally conductive interface pad designed for use between heat generating components and their heat sinks. These materials conform to surface irregularities under moderate application pressures to fill air gaps and enhance heat transfer. Specifically, the material selected is an electrically non-conductive, boron-nitride-filled silicone elastomer best suited for applications with pressures from 5 to 100 psi (0.03-0.69 MPa), where high thermal performance is required.

“Our team works closely with the customers to select materials that closely fit the environmental and physical requirements of the application,” said Fran Berardinis, Operations Manager. “I am extremely proud that Fabritech’s gasket solutions have been selected by leading defense contractors for mission critical requirements.”

Fabritech, Inc. is a high technology, high capability company committed to exceeding client expectations; our expertise encompasses the entire range of Aerospace and Defense, including applications for Land, Sea and Space.

Our products include seals, gaskets and O-Rings manufactured from MIL-STD-83528 approved materials, including: thermally conductive elastomers, oriented wire in silicon, woven mesh, wire mesh, and microwave absorbing materials.

Fabritech, Inc. Ships Custom EMI Gaskets to a Leading Defense Contractor for UAV’s (Unmanned Aerial Vehicles)

West Chester, Pennsylvania – Fabritech, Inc., part of the Integrated Polymers Group, a manufacturer of precision engineered custom EMI, RFI and Thermal Gaskets, recently shipped an order of custom EMI gaskets to a leading defense contractor to be integrated into UAV’s (Unmanned Aerial Vehicles).

The gasket material chosen for this project is a silver-plated, copper-filled silicone and MIL-STD-83528 Type A compliant. It resists the highest level of EMP induced current and is the military gasket material of choice in non-corrosive environments. A feature of the material is its excellent resistance to compression set over a wide temperature range, resulting in years of continuous service. In addition to EMI shielding, these materials provide an environmental or pressure seal if required.

“Our gaskets and O-Rings are made in the USA. We work in partnership with our customers to select materials that closely fit the environmental and physical requirements of the applications,” said Fran Berardinis, Operations Manager. “We strive to provide excellent products and support for mission critical requirements.”

Fabritech, Inc. is a high technology, high capability company committed to exceeding client expectations; our expertise encompasses the entire range of Aerospace and Defense, including applications for Land, Sea and Space.

Our products include seals, gaskets and O-Rings manufactured from MIL-STD-83528 approved materials, including: thermally conductive elastomers, oriented wire in silicon, woven mesh, wire mesh, and microwave absorbing materials.