The US Navy is testing the use of small remotely operated vehicles (ROVs) to perform inspections of ballast tanks without draining the tanks first. If successful, the technology could help reduce shipyard maintenance times and costs, a key priority for the service.
On February 16, a team from the Puget Sound Naval Shipyard demonstrated the use of a VideoRay Pro 4 ROV to inspect ballast tanks, using the amphibious assault ship USS Iwo Jima as a test site. The yard has been using the ROV for tank and nuclear void inspections for several years now, and with its success, the Navy is exploring the possibility of expanding its use to regional maintenance centers and other maintenance facilities.
A board Iwo Jima At the Mid-Atlantic Regional Maintenance Center, 20 personnel from Puget Sound Naval Shipyard, Southeast Regional Maintenance Center, Southwest Regional Maintenance Center and other facilities observed the ROV navigate around the tank.
“We were able to get a pretty clear and accurate view of the inside of the tank,” said Ty Curtin, division manager for tanks, voids and structure at the Mid-Atlantic Regional Maintenance Center. “We were able to see a lot of items in this tank that have been documented previously by our assessors. When the vessel goes into availability this summer, we will be able to go in and compare what we saw today.
Tank inspections and overhauls are often performed during maintenance availability. The process of draining a tank, drying it out, and performing a gas-free assessment takes a lot of time, money, and man-hours.
“There’s a whole process we have to go through before we can get someone into a tank to do an inspection which most of the time only takes a few hours,” said Kevin Baum, Ventilation and Control Branch. damage from the Mid-Atlantic Regional Maintenance Center. To manage. “On the [destroyers and cruisers]where stability is key, having the ability to conduct an accurate and descriptive inspection or verify a specific issue without having to go through this preliminary process could be a game-changer for us.
Using a submersible ROV drone in a filled ballast tank is relatively unusual, but flying drone video inspections are gaining popularity in the marine industry – especially in the offshore sector, where they can replace structural inspections of rope access. They are the subject of active R&D activity for class societies – such as DNV and ABS – and for large shipowners, such as Polar Tankers and CMA CGM.