Page 175 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

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CHAPTER 8 Cables and Connectors
8.9
8.10 8.11
8.1
8.8.13.2 Kellemsgrip...................................................................................................210 8.8.13.3 Lace-upgrips.................................................................................................211 8.8.13.4 Helicaltermination.........................................................................................211 8.8.13.5 Mechanicaltermination..................................................................................211
8.8.14 Bonding...............................................................................................................213
8.8.14.1 Vulcanized rubber splice................................................................................. 213 8.8.14.2 Transfer-molded rubber splice ........................................................................ 213 8.8.14.3 Castable polyurethane resin splices................................................................. 213 8.8.14.4 Coldsplice.....................................................................................................214
8.8.15 Cabledesignsummary..........................................................................................215
Testing and troubleshooting.........................................................................................................215
8.9.1 Electrical testing, troubleshooting, and predeployment checkout ................................ 215 8.9.2 Ohm sift or continuity test....................................................................................... 215 8.9.3 MegOhm testing or insulation resistance .................................................................. 216 8.9.4 Hi-Pot or voltage withstand test ............................................................................... 216 8.9.5 A time-domain reflectometer ................................................................................... 216 8.9.6 Mechanical testing and troubleshooting.................................................................... 216 Tips from the field.......................................................................................................................218 Summary....................................................................................................................................219
Introduction
Underwater cables and connectors provide system flexibility, ease of service, and other design advantages for undersea equipment—including ROVs. The primary purpose of underwater cables and connectors is to provide a conductive path, without leakage, in a pressure-resistant or pressure- tolerant package. Cables and connectors allow for simple system configuration (Figure 8.1).
Underwater connectors are used to connect the umbilical to a tether management system (TMS) and then from the TMS to the ROV. In addition, these items interconnect separate components on the ROV to form a functioning integrated system. Connectors enable these components to be dis- connected for easy removal for servicing, repairs, or upgrades.
A mated connector pair forms a unique small pressure case. All pressure case design criteria then apply. A bulkhead connector becomes a mechanical part of a pressure hull and thus should be looked at critically.
It is important to the success of any subsea project that both end users and manufacturers speak the same language from the beginning.
In this chapter, readers will:
1. Learn the language of underwater cables and connectors common to the underwater industry;
2. Learn a practical approach to specifying underwater cables and connectors for their specific
application; and
3. Raise their understanding of what can be expected from cable and connector manufacturers.