As oil and gas exploration pushed farther offshore, it also went to increasingly lower depths. In the history of offshore drilling, this started at 30 ft depths off the coast of California, to today, where depths of 10,000 ft and more are possible. These increases in depth have been made possible by innovative technologies. One of these innovations was the introduction of the remotely operated vehicle (ROV) for underwater exploration and development. While saturation diving has been performed to depths of 2,000 ft, it is not common and brings many health and safety requirements.
Today, divers are still used down to 300 ft, with anything beyond that depth performed by an ROV. Operated from a control van on the surface of the water, ROVs have become an integral part of the offshore oil and gas industry. As a leader in manufacturing office modules for the offshore industry, Armoda has produced ROV control van modules for vessels and facilities in the offshore oil and gas industry. This article will review what an ROV is, and what to consider when renting or purchasing an ROV control van module.
Remote operating vehicles are robotic underwater machines designed to be highly maneuverable and perform tasks that would be too dangerous or impossible to be performed by a diver. Each ROV is designed for a specific purpose, meaning they can vary in size and shape. For example, they could be the size of a microwave or as big as a van. They are broken into two types, work class, and observational class. As the names suggest, each is designed for specific purposes and is designed to perform these tasks.
Work class ROVs are equipped with manipulators, or mechanical arms, that can perform maintenance and repair tasks. There are even heavy work class ROVs that are designed for deeper waters and are capable of lifting multiple-ton objects.
Observational class ROVs are equipped with multiple cameras, microphones, and lights to give the operator a view of the underwater equipment. They are used for surveying and inspections.
The ROV control van is the operational center for all the equipment and personnel used to run the ROV. The size and equipment held within the control van vary, depending on the type and use case of the ROV being deployed. Control vans are typically housed within 20 ft offshore modules that have been specially outfitted to meet the needs of the ROV. The functions of the ROV can be broken up into multiple operators, each with their area of expertise, such as pilots, navigators, and video.
Three main factors determine the correct size of a control van for any given project. The size and amount of the equipment necessary to operate the ROV, the number of personnel required to run the ROV, and the available space on the deck of the vessel/facility. Knowing these three factors will allow you to determine the correct size unit to fit your project. Most control vans are around 8’ x 20’, with larger units utilizing a multi-module configuration with interior corridors.
When it comes to certifications for ROV cabin vans, there are many factors that can impact the certifications that the unit may need. Determining the main certifications that are required will be based on the type of vessel or facility and where its operating, as well as its placement on the deck. If the vessel operates under a US flag or in US waters, the control van module may require ABS-certified modules or USCG-certified modules. Depending on the vessel class and flag, the control vans may require a more common international certification for modules, such as DNV. Other certifications may also be applicable, but these typically encompass the required specifications to meet those other certifications.
Other certification requirements are decided by where the module will be installed on the deck. For example, if placed near hazardous areas on offshore oil and gas vessels and facilities. Like the ABS/USCG and DNV certifications, separate certifications are used in the US and internationally. The US uses the Class/Division/Group system, which is designated Division 1 or Division 2. The international standards use zones designated Zone 1 and Zone 2. ATEX and IECEx hazardous area standards and directives have a significant impact on the design standards that may be required for ROV cabins operating in hazardous areas. It's important to understand the differences between Divisions and Zones, a topic we've also explored. Once the module’s location on the deck is decided, the correct certification can be determined.
This summary should provide a base of knowledge on what both an ROV and ROV control van are and what to consider the next time a control van module is needed on your vessel or facility. But, do you know all about the different offshore module certifications that can apply to an offshore module?