Customer Overview
Sealing Devices’ customer provides essential satellite communications systems to many leading government and military agencies and defense contractors.
Customer Problem
The customer needed help designing an antenna radome to allow for communication, navigation, and data transmission while remaining resilient under the harsh conditions of aerospace operation.
- Environmental Conditions: The system is required to withstand the extreme temperatures (-50°C to +150°C), vacuum conditions, and radiation exposure typical of spaceflight, while remaining water- and dust-tight.
- Physical Constraints: The radome is designed for mounting within the nose of the craft, and so had to meet strict requirements for aerodynamics, installed footprint, and low weight.
- Material Compatibility: All materials used in the radome, including seals and vents, needed to be thoroughly evaluated for compatibility with the expected temperatures, as well as outgassing and corrosion requirements.
- Electromagnetic Compliance: None of the materials in the intended signal path could appreciably interfere with the signals being sent and received. The signal processing electronics, on the other hand, needed shielding from any potential signals not coming directly from the customer’s antenna.
Customer Requirements
- Low outgassing
- Lightweight materials
- Watertight sealing temperatures
- Thermal Management
- EMI Shielding
- Venting
Solution Partners
How did Sealing Devices Get Involved?
Additionally, since Sealing Devices is AS9100 certified and ITAR registered, they were able to support sales into the aerospace and defense sectors. The Sealing Devices Applications Engineering team worked with the customer to review the design and make solution recommendations.
Sealing Devices’ Solution:
To create an environmental seal on the radome, Rogers closed-cell silicone foam was recommended for its low outgassing and resilience from -55°C to 200°C; this foam is easily compressible and has a high rebound, allowing for a vibration-resistant seal.
The antenna circuitry was enclosed within the radome using a conductive elastomer o-ring and connector gaskets from Parker Chomerics, which provide shielding from electromagnetic interference and an extra layer of environmental protection.
Sealing Devices also provided silicone gap fillers from Chomerics to support heat transfer between the electronics and a heat sink. Since the radome will undergo regular altitude changes, a Gore protective vent was installed on the enclosure wall to prevent excessive stress on the foam seal while maintaining watertightness.
Results:
Sealing Devices fabricated sample parts which were customized for the application and provided to the customer for fitment and performance testing.
Pending their approval, these parts will be produced at volume and combined into kits for future radome production.
Common Application Requirements
- Low outgassing per NASA
- Low weight / light-weighting
- Extreme pressure changes, down to full vacuum
- Water/weather protection
- UV and ozone resistance
- Thermal management
- EMI shielding
- Extreme temperatures
Sealing Solutions
- O-Rings
- Die-cut gaskets (solid or cellular)
- EMI shielding elastomers and foams
- Thermal interface materials
- Protective Vents
- Adhesives, tapes, sealants, and potting compounds