1. Conauctor 



2. Extruded strand shielding 



3. Polyetliylene insulation 



4. Tape 



5. Copper shielding 



6. Fill waterproof jute 



7. Binder mylar tape 



8. Polyethylene jacket 



9. High-strength galvanized steel armor 

 10. High-density polyethylene jacket 



over each armor wire 



Figure 18. Typical cross section of selected marine cable. 



One of the first devices used for sealing a cable penetration on a deep 

 submergence pressure hull was a 1.1-inch-diameter, four-conductor cable sealed 

 with a stuffing box design. The packing was composed of four or five layers 

 of flax packing pressurized from both ends of the stuffing box with gland nuts. 

 The seal was successful down to about 3,000 feet. 



Primary and secondary cable seals are mandatory requirements for all 

 submersibles. The primary seal is located outboard of the pressure hull and 

 the secondary seal is located inboard of the hull. With respect to primary 

 cable seals, the use of watertight connectors is recommended. The connectors 

 would provide a positive water dam in case the cable is damaged or severed. 

 Connectors also satisfy the secondary cable seal requirement by providing a 

 positive water dam inboard of the pressure hull. The use of connectors for 

 hull penetrations allows the testing of such fittings under pressure prior to 

 deployment and provides junction points for the cable conductors. This 

 eliminates the need for junction boxes and provides a test point for checking 

 circuits served by the connectors. 



Figure 19 shows a multiple-conductor hull fitting which has been 

 used on Navy submarines. This fitting will withstand nominal shock loadings. 

 As noted, the outboard watertight connectors are located radially around 

 the body of the fitting to accommodate a maximum number of cables. 



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