US navy adopts hydrogel bulkhead seal technology

The seal design means that it does not have to be in contact or rotate with the shaft, reducing wear. A hydrogel embedded foam activates a lip seal in emergencies, with the foam helping to absorb water from flooding and the lip seal stemming leaks.

Midé Marine noted that the HydroActive bulkhead shaft seal’s lack of contact on the shaft during normal operation eliminates premature wear, reduces installation and operation requirements and ensures that it will effectively seal when needed.

The seal supports non-standard propulsion systems including high-speed composite shafts. They can be used on shafts that are inclined or are not perpendicular to the bulkhead.

The seals will be installed on more than 50 US naval ships in total, accounting for nearly 250 seals to be installed on newbuild vessels or retrofitted. Midé offers a version of the seals commercially and is pursuing other applications of the technology.