Galoshes keep feet dry. Specialist materials group Raychem has borrowed the idea to keep metal joints corrosion-free.
Targeting marine applications, the GelTek silicone rubber boot can be moulded to protect any type of metal joint. The boot is filled with a silicone rubber gel developed by Raychem, cross-linked to stabilise the material at temperature and prevent it flowing away from the joint.
The boot, tested by the US navy, is being used to protect flanged joints in waveguides used to transmit high-frequency electromagnetic energy.
Another system protects the latest on-board Aegis radar equipment several feet in diameter, big enough to be set down in the ship’s superstructure.
A small boot protects coaxial connectors while a peel-off, gel-only, version provides a waterproof barrier between fastenings and the bulkhead.
Where EMF protection is needed, corrosion-resistant Monel mesh provides an earthed grounding between the gel and two gaskets.