Parker Chomerics Developed EMI Shielding Solution
To provide an effective EMI and environmental seal to ingress and egress hatches, the following materials are being designed into the application.
Parker Chomerics application engineers, in partnership with the customer’s design team, determined that CHO-SHIELD 2002, an electrically conductive polyurethane coating with a copper conductive filler would help to aid in corrosion resistance. This material is specifically formulated to offer corrosion protection for enclosure flanges which mate with EMI shielding gaskets. It also offers excellent chemical resistance to hydraulic fluids and motor oils.
To help fill seams in gaps and around rivets, a silver-plated aluminum filled silicone electrically conductive sealant called CHO-BOND 1075 was used to give additional EMI protection and to provide an adhesive bond for the gasket.
A robust dual gasket configuration, called a co-extrusion, made from CHO-SEAL 1298 material, containing both a silver-aluminum filled electrically conductive silicone gasket alongside a non-conductive military grade environmental gasket was also chosen. This gasket was positioned around the entrance hatches to ensure compliance with both EMI and environmental requirements.
In other applications on the vehicle, CHO-SEAL 1298 EMI shielding gaskets were custom made for use with multiple periscopes cameras. Several connector gaskets were also fabricated out of CHO-SEAL 1298 material and were used to shield electronic hardware.
All air intake and exhaust ducts required circular steel EMI honeycomb vents, fitted to allow air flow while providing an EMI shield.
The Parker Chomerics applications engineering team worked closely with the customer design team to meet rigorous testing procedures and ensure compliance of all specified technologies.