INGENIEUR
Burial Systems Available Configurations General Characteristics Sleds
Free swimming ROVs
Tracked Machines
Ploughs
• Jetting systems
• Rock wheel cutters
• Chain excavators
• Dredging systems
• Jetting systems
• Dredging systems
• Jetting systems
• Rock wheel cutters
• Chain excavators
• Dredging systems
• Conventional narrow cable ploughs
• Advanced cable ploughs
• Modular cable ploughs
• Rock ripping ploughs
• Vibrating share ploughs
Table 1 : Overview of subsea trenching technologies ( Data from BERR [ 7 ]).
These are routinely deployed from jack-ups or barges and either possess subsea power or utilize power systems which are installed on the barges .
Free swimming ROVs are generally conducted and controlled from a barge or a host vessel such as a Dive Support Vessel ( DSV ). They normally work in post lay burial fashion , and are mainly suited for shorter distances with operating depths that can reach approximately 2500m .
Tracked machines are controlled via a tether connected to the host vessel . Interestingly , not all these machines operate in post lay ; few exceptions , such as the LT1 , have the ability to achieve cables laying and burying process concomitantly . Their efficiency can be extended to water depths up to 2000m .
Cable ploughs are towed systems usually operated from a host vessel with enough bollard pull to allow a continuous cable burial progress . In principle , the cables are buried along with the laying process . Cable ploughs are suited in a wide variety of soils and are typically deployed for longer distances of operation . Ploughs can operate in shallow and deep-water conditions ( up to 1500m ).
Figure 1 : Range of capabilities of different trenching technologies ( adapted from Brunning and Machin [ 8 ]).
64 VOL 91 JULY-SEPTEMBER 2022