Underwater Splicing of SD Coaxial Cable--FY78 Progress.
Rept. for Oct 77-Sep 78,
CIVIL ENGINEERING LAB (NAVY) PORT HUENEME CALIF
Pagination or Media Count:
Splicing of SD List 1 coaxial cable on the seafloor has been demonstrated to be feasible using a greasegel filled coaxial splice. Experimental electrical models fabricated for underwater mating have been operated successfully at 6,000 VDC and 5,000 psig ambient pressure with leakage currents less than 1 microampere. Impedance mismatches of the electrical models were about 0.4. The search for a compatible dielectric grease for use with the SD cable splice identified a gelling agent Cab-O-Sil which can be used to gel liquids to a grease-like consistency. Castor oil, available in liquid form only, has some unique properties desirable for SD cable splicing applications. These are 1 low water absorption about 1, 2 little or no change in dielectric constant with about 1 water absorption, compatibility with high density polyethylene and ability to gel using Cab-O-Sil. Electrical splice models filled with gelled castor oil have been mated several times at 5,000 psig ambient pressure in seawater at 8C. The splice was subjected to 6,000 VDC with no high voltage breakdown and leakage currents were less than 1 microampere in each case. Due to lack of internal seals, the splice failed after a 30 day duration in the pressure vessel because seawater was forced into or migrated to the cable and splice interface area. The tests do show the feasibility of the underwater splicing concept of SD coaxial cables. Author
- Electrical and Electronic Equipment