Pressure Hull Glands (PHG) are the recognised method used for passing cables through submarine hulls. On submarines, various external equipment is located under the upper casing. This equipment, such as sonar, fibre optical systems, mast raising gear etc. will require cable or connector terminations, which will necessitate penetrating the hull in order to reach the internal equipment stations.
The hull glands through which they pass are classed as Category 1 which means that they have a critical effect on It, therefore there is a requirement that these glands must be designed to the very highest of standards. Any design review which results in even the slightest of modifications will require the re-designed gland to undergo further extensive and rigorous acceptance testing.
All Hydro Group submarine pressure hull penetrators / glands are designed in-house by our team of skilled development engineers.
The two standards of Pressure Hull Glands (PHGs) currently in use are the Imperial 2 3/8 used in earlier Swiftsure and Trafalgar class submarines and Metric 62.95mm which is used on Vanguard submarines and Astute SSN submarines. These glands have various cable entry configurations including multi-core, paired, screened paired, tripled, coaxial and fibre optic types.
Hydro Group has worked closely with the Ministry of Defence to develop a fibre optical copper configuration to include both existing Pressure Hull Glands (PHG) standards. PHG's of this type have now been successfully deployed on S, T and V class submarines.
These fibre optical systems are being utilised in ship to shore communications but further development is likely in the near future to include external equipment operation when the vessel is on deployment.