The Development of a Cable Termination System for Deepwater Applications

FULL JURNAL

As oil and gas production projects move into deeper waters, new key enabling technologies are required to terminate electrical, optical and hybrid subsea cables. Two failure modes have been identified using current commercially available termination technology in deepwater applications; core element collapse into an atmospheric breakout region and wicking of the compensating fluid from the termination into the interstices of the cable elements. Either failure may lead to partial or catastrophic failure of the termination. Each failure mode can be directly linked to the interaction of the cable elements with the pressure-balanced dielectric fluidfilled splice region in the termination.
Both of these failure modes have been encountered in the recent past during the installation phase of ultra-deepwater developments. In each instance, an understanding of the failure mode led to the development of design modifications that were qualified and successfully deployed. The difficult lessons learned from these experiences have resulted in new design considerations and more rigorous qualification procedures during the development of cable specific Field
Installable Termination Assemblies (FITAs). These lessons have also been cause to rethink the design philosophy of cable terminations. Ocean Design, Inc. (ODI) has embarked on a design program to eliminate the limitations of the current technology and increase the reliability of their terminations.
The result of this effort is the FACT (Field Assembled Cable Termination) system, a modularized termination system that completely isolates the cable’s internal elements from all pressurized
fluid interfaces.