A subsea vessel is a specialist type of ship that is purposely designed to carry out underwater operations for offshore energy projects. They are built in a way which allows them to operate even in harsh marine environments which have high waves, deep waters, and extreme weather. In this article, we explore subsea vessels in detail, looking at the critical role that they play in the offshore industry.
What are subsea vessels used for?
Let’s start by looking at what subsea vessels are used for and the role that they play in offshore energy projects. Subsea vessels are most commonly required for:
- Underwater construction tasks required to get offshore projects fully operational, such as pipelay, subsea infrastructure construction, and installation.
- Underwater maintenance and repair tasks required for offshore projects to operate effectively and safely, including underwater surveys and inspections.
- Underwater exploration which is required during the planning stage of offshore projects, such as seismic studies to locate possible oil and gas reserves underneath the ocean floor.
What types of subsea vessels exist?
Subsea vessels carry out extremely precise operations in very challenging conditions using highly sophisticated technology. Several different types of subsea vessels exist, each designed to carry out very specific specialist task(s). Let’s look at a few different types of subsea vessels, including the unique functions and capabilities of each:
- ROV Support Vessel (RSV)
RSVs are vessels which support the operation of Remotely Operated Vehicles (ROVs). They can be used in water of depths up to approximately 4,000m. - Construction Anchor Handling Tug Vessel (CAHTS)
This is a type of Offshore Support Vessel (OSV), equipped with a subsea crane or A-frame, and/or a permanent ROV, used to lay and retrieve anchors, as well as to position larger vessels. - Diving Support Vessel (DSV)
DSVs are vessels used to carry out diving operations in harsh conditions in open water. More specifically, DSVs are designed to be used under/around oil platforms, and related offshore infrastructure, for tasks such as underwater inspections and maintenance. - Multipurpose Support Vessel (MPSV)
MPSVs are used to carry out a range of maintenance and supply tasks specifically for the offshore oil industry. Typically, these ships are used as a floating platform while subsea service providers complete operations and are kitted out with sophisticated equipment such as cranes, moonpools, and helipads.
- Construction Support Vessel (CSV)
CSVs are specialist vessels used for offshore oil & gas and offshore wind projects. They assist with a range of construction-related tasks, such as trenching and plough work. - Well Stimulation/Intervention Vessel (WINT)
These specialist vessels are designed and equipped to carry out deepwater interventions that help to restore production from underwater wells. - Cable Lay Vessel (CLV)
These large ships lay cables underwater – on the seabed – in order to establish communication and power networks between different offshore structures and/or different parts of the world. - Heavy Lift Vessel (HLV)
These vessels feature large cranes, which are capable of lifting and installing even the heaviest of offshore structures. - Pipelay Support Vessel (LAYSV)
Mainly used in the Oil and Gas industry, these vessels are equipped to carry out both flexible and/or rigid pipelay operations.
Why are subsea vessels important for the offshore industry?
Subsea vessels are extremely important to the offshore industry, particularly in sectors like oil and gas, renewable energy (e.g. offshore wind farms), and underwater infrastructure. They are indispensable across every stage of offshore projects – from planning and development to construction, production and maintenance.
Put simply, traditional ships just cannot do what subsea vessels can. Subsea vessels are specifically designed to carry out highly specialised functions while operating in harsh conditions and deep waters. Normal vessels do not have the equipment and/or capabilities of doing what subsea vessels can, and so without them, offshore projects would not be possible. This is becoming increasingly true as offshore drilling starts to move into deeper and more remote waters, requiring larger and more sophisticated vessels and equipment. Subsea vessels are designed to keep up with the complexities of this evolving industry and provide the crucial logistical and support services needed for its success.
How can Clarksons support subsea vessel operations?
Leaders in the field, Clarksons’ specialist Subsea Vessel Operations Team can support your subsea vessel operations. With in-depth knowledge of the full range of subsea-related segments, the team can lend their expertise to projects of any scale and complexity.
Clarksons’ Subsea Vessel Operations Team has extensive experience in supporting both Oil & Gas and offshore wind clients, providing support with chartering, projects, S&P, newbuilding and mission specific equipment. They offer subsea vessel services including expert brokerage services, market insights, and logistical support to ensure the success of your offshore project(s). And with coverage of all major global markets, including NSEA, APAC, West Africa, USG, and Brazil, the team can provide a reliable service wherever your project is located.
