Laser scanning inside ballast tanks and other enclosed environments
Laser scanning provide the ability to capture data in the dark. Even in the dimly lit areas of the Ballast Tanks, the scanner perform effortlessly offering a “night vision” view of the site. The operation collects millions of data points that provided a single point cloud of the project, more than enough information for the design team for the BWTS (Ballast Water Treatment System) retrofit.
During the designing and construction stages of a ship, the ballast tanks are introduced at various locations for maintaining the stability of the ship during the sea voyage.
As ships get bigger in size and the cargo carried by the vessels varies one port to another (due to global economics, ship condition, local voyage requirements etc.), water ballast tanks are used to compensate for maintaining the trim and stability of the vessel for a safe sea passage.
Ballast water tanks laser scanning
Enclosed spaces are a fundamental component to the ship’s structure and are circuitously critical for the economics of running the shipping company.
A large part of the ship’s earnings in the form of cargo (dry as well as wet) is exhumed from large void spaces commonly known as ‘tanks’, within the configuration of the ship.
In fact, the steel tanks aid with the ship’s stability, especially when stability is associated with juggling between filling and discharge of fuel oil or water as ballast/domestic.
Considering the immense significance of these spaces, they have to be regularly maintained.
Planned inspections and regular cleaning/repairs would be best for ascertaining the top shape of the ship’s hull and its components.
Laser scanning can be conducted in absolutely no light. This makes it possible to measure and see things in places of absolute darkness. When scanning in dark conditions, the scanner is unable to pick up color unless artificial light is added, but the resulting point cloud imagery looks almost like night vision. Everything that was once very dark will be brightly visible in the 3D model.
Laser Scanning of Double botton Ballast Water tanks
Laser Scanning of botton and side Ballast Water tanks
Locations of Ballast Tanks on ships
The water ballast tanks are provided at different locations depending upon the type of the ship. Following are some of the most common locations for construction of ballast tanks on ships:
The tanks are located on the topside corner of the ship. The topside tanks are triangular in shape fitted with wings on both sides of the cargo holds. They are more common in bulk carrier ships and are constructed using transverse frames arranged in the following ways:
A deck transverse under the main deck which supports the deck plating
Bottom transverse which forms the part of the supporting frame for the bottom area of the topside tank
Side transverse forms the part of the structure for supporting the side shell plating of the tank, which is kept in-line with the side shell frames within the cargo holds (in single skin bulk carriers)
Double Bottom (DB) Tanks
The double bottom of the ship is a safety feature to avoid ingress of water in case of grounding or collision. These void spaces are used to store ship ballast water to stabilize the ship. The double bottom tanks are located between the forward part (till collision bulkhead) to the aft peak bulkhead, dividing the engine room. In some ships, such as container and bulk ship, the double bottom space is divided transversely into three sections (instead of two). This is done to provide a cofferdam in the centre known as the duct keel which are used to carry ballast and bunker tank valves, and pipings for ships ballast tank and bunkering system.
Ballast tanks 3D Laser scanning , BWTS Retrofit
Fore and Aft Peak Ballast Tanks
The fore and aft peak ballast tanks are provided to perform precise trimming operation of the ship. To achieve the required trim these tanks are hardly filled partially to avoid the free surface effect of the liquid
The construction of the fore and aft peak tanks is different from the other ship’s ballast tank as their shape is pretty irregular due to the location and their shape highly depends on the bow and the stern design of the vessel.
The design of these ship ballast tanks is narrow at the bottom end, and as the tank moves upward, the width of the tank increases significantly. The tank breadth corresponds to the breadth of ships’ hulls.
3D Laser Scanning of side Ballast Water tanks
Laser Scanning of Ballast Tanks for BWTS retrofit