FEATURE
MODULAR CONNECTIONS IN SUBSEA CABLE PROJECTS:
Can Subsea Telecom Benefit From O&G and Scientific Connection Methods? BY ROBERT THOMAS, JEREMIAH A. MENDEZ, AND LARA D. GARRETT
T
he subsea cable systems used for traditional commercial telecom applications have relied on permanent cable connections for many decades. The polyethylene over-molded cable-to-cable joint is the workhorse of such undersea cable installations, facilitating system construction and integration in the factory, and then reliable cable installation and at-sea repairs. The offshore Oil & Gas and Scientific communities, alternatively, have relied upon wetmate and dry-mate connectors to support their operations that require a high degree of modularity and reconfigurability. For more than 20 years, submarine telecom cables have been employed to serve Oil & Gas and Scientific requirements, and these systems increasingly make use of in-line fiber-optic connectors. In this article, we will review and discuss applications that combine traditional subsea telecom cables with these modular connection elements. The performance of technologies, products, and installation techniques supporting these reconfigurable connector applications have been steadily improving. System-planners and architects may use these technologies that offer more flexibility and modularity at specific locations in the system. We will define some remaining areas of development that could lead to wider
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SUBMARINE TELECOMS MAGAZINE
acceptance and utilization of these technologies across the undersea telecom industry generally.
OVERMOLDED JOINT
The “overmolded� joint has supported fiber-optic systems since the 1980s and coaxial systems even earlier from the 1960s. Polyethylene injection molding of the entire joint-box provides encapsulated jointed cable lengths, for example between repeater and branching unit couplings. The encapsulation provides electrical insulation and water ingress protection. This is a reliable and highly repeatable process, used in the factory for system assembly, and shipboard for installation and maintenance. The joint supports the low-loss splicing, storage, and protection of multiple fibers and restoration of the electrical conductor between spliced ends. While submarine telecom cable suppliers all maintain a proprietary joint design, there is an agreed-upon degree of standardization. Through the efforts and activities of the Universal Jointing Consortium (UJC), the submarine cable community can therefore use a common suite of shipboard equipment to facilitate the repair and interconnection of the cables from different manufacturers in maintenance scenarios. The UJC collaborates on universal jointing (UJ),