BREAKING WITH CONVENTION A DIFFERENT WAY OF LAYING SUBMARINE CABLES by Michael Jones The Recent Past For SMD, as the leading supplier of trenching equipment to the submarine telecoms industry, the last five years has seen staggering changes in level of production and pace of technology development. Some figures that illustrate the first point are that in it’s first 15 years SMD built 27 subsea systems for telecoms; in the past 5 years we have built an amazing 43 machines. These have included ploughs which could bury cable up to three times deeper than a standard plough for little increase in size. This plough, with the help of a unique jetting system, could go deeper and faster in sand, and with a similarly unique ripping system, could extend cable protection
using a ploughing into rock. And these are to name but a few of our innovations in cable lay and burial over that period.
The Present Reality At this moment, most of these ploughs and some of the ROV’s are laying idle. We don’t anticipate a recovery in this sector of the telecoms market until well into the second half of this decade. So, what is a telecoms supplier supposed to do in the meantime? Fortunately, as a relatively small company based around a core of innovative and flexible engineers, we have been able to seek and exploit other outlets for our talents. In applying our thinking to the
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renewable energy and military markets we have developed technology, which has potential for future application to submarine telecommunications and is the subject of this article.
Breaking with Convention Traditional practice in the submarine cable industry is to lay the cable from a surface vessel and to either simultaneously or in a separate, later operation, bury the cable. When SMD were approached by Mayflower Energy, a newly established offshore wind farm installer, to build a vehicle for burying power cables, we devised a system, which brings together proven elements from more conventional equipment to create a uniquely capable machine. This has been done by carrying the spool of lay cable on the vehicle rather than the surface vessel. The self-propelled tractor carrying the spool of cable is able to simultaneously lay and bury an entire interconnecting cable between adjacent wind turbines. Whilst it is performing this operation, it’s host vessel, the Mayflower jackup vessel Resolution, can carry on with it’s primary task of installing the topside wind turbine.
The Detail The Lay & Burial Tractor (LBT 1) is large by telecom construction vehicle standards, weighing in at almost 60 tonnes (132,000lbs)