The Development of a Cable Termination System for Deep Water Applications

Abstract

As offshore developments are pushed into deeper waters, new enabling technologies are required to terminate electrical, optical and hybrid cables. Recent experience has shown that, depending upon cable construction, two failure modes are possible.Firstly, in many cable terminations, the individual cores of the cables pass from an atmospheric cable breakout chamber into a dielectric fluid-filled pressure-balanced splice chamber. Even supported core elements can collapse into the atmospheric cable breakout when used in deep water applications, resulting in damage to the conductors. Secondly, many cable terminations have a single sealing element separating the oil or gel-filled volume from the cable and conductor interstices which are, in many cases, atmospheric. If this sealing element is compromised, the resulting venting of the oil can lead to failure of the termination.A new, key enabling cable termination technology has been developed to extend the operational depth and significantly increase the reliability of cable terminations. This modularized system completely isolates the cable elements from the pressure-balanced splice chamber and ambient environment. This approach to cable termination eliminates cable-dependent design limitations and common mode/single point failures. This paper provides an overview of the current designs and typical failure modes. It then provides a description of the new termination system and the solutions it offers.