A new remotely operated vehicle system (ROV) has been developed with the capability of actuating a blowout preventer’s (BOP) shear rams without the need of additional equipment. The ROV, made by FMC Technologies’ Schilling Robotics, is the 3rd generation of the company’s Ultra Heavy Duty (UHD) ROV and was introduced for the first time this week at SPE’s Offshore Technology Conference in Houston.
In addition to the typical work-class duties, the UHD III ROV was designed to be a backup system for situations when an operator loses topside control of a BOP and requires a manual override or a secondary hydraulic system to be deployed subsea. Conventional solutions call for accumulator pumps to be placed on the seafloor nearby the BOP, or for pumping equipment to be installed onto the underbelly of the ROV. Hamish Stewart, a senior sales manager at Schilling Robotics, said the new design is capable of closing the BOP in 45 seconds and is the only work-class ROV on the market that meets the American Petroleum Institute standards for secondary BOP intervention. With a conventional seabed or ROV-mounted pumping system, “you get the volume you need to actually start closing the BOPs, and then you have to back it up with a high-pressure pump,” Stewart said. “That is time consuming.”
FMC’s new 250-hp vehicle eliminates the need for any extra equipment and saves operational time by putting a high-pressure pump inside the ROV frame. The onboard hydraulic pump is capable of delivering liquids at a rate of 50 gal/min at 5,000 psi and requires no ramp-up time to achieve the maximum pressure or flow rate. There are two onboard reservoirs, each with a capacity of 100 gallons and capable of holding a broad range of fluids including water-based, oil-based, and chemical-based solutions for various operations, including the pumping ofmethylethylene glycol for methane-hydrate remediation in flowlines.
Other advancements based on earlier versions of the UHD vehicle are making their debut as well, like an upgraded station-keeping package that seeks to lessen the time spent on basic manipulator operations. In some cases such an ordinary task could take several minutes, but in more challenging situations it can take several hours to complete. To solve this problem, the company developed what it calls “tool dynamic positioning” to enable the ROV to automatically grab tools at the pilot’s command. As the ROV approaches a tool or object of interest, the onboard computer will identify the object and pick it up without human at the controls. “It is not going to replace the ROV operator; it is complimentary,” Stewart said. “There are situations out there where it is very difficult for the operator to work the vehicle and actuate the manipulators.”
Another upgrade involves high-definition cameras, which have become a standard feature on most new ROV systems even as developers have been restricted in how many they can place on a vehicle because of the high amount of data the cameras transmit. The UHD III compresses the video data and transmits it topside via Ethernet, which allows for several HD cameras to be installed rather than one or two. Following the successful completion of sea trials, ROV service company C-Innovations announced it has ordered six of the UHD III vehicles for its fleet, with delivery expected early next year.
Trent Jacobs is a Technology Writer for the Journal of Petroleum Technology.