Crude Oil which nearly contributes to 30% in the energy basket of the world is transported in containers having more than 3, 00,000 deadweight. A tanker's deadweight is a measure of ship's carrying capacity in tons. It includes both the weight of the cargo (in the case of ship’s carrying crude the cargo is the crude oil) and the weight of the fuel the tanker carries for her own propulsion purposes. Crude containers come in an enormous range of sizes like as follows:
· ULCC :- above 3,20,000 tons Deadweight
(Ultra large crude containers)
· VLCC :- 1,60,000 to 3,20,000 tons Deadweight
(Very Large Crude Containers)
· Suezmax :- 1,20,000 to 1,59,000 tons Deadweight
· Aframax :- 80,000 to 90,000 tons Deadweight
· Paramax :- 50,000 to 80,000 tons Deadweight
· Handymax :- Approx. 45,000 tons Deadweight
Oil tankers come in two basic types, the crude carrier, which carries crude oil, and the clean products tanker, which carries the refined products, such as petrol, gasoline, aviation fuel, kerosene and paraffin. It must be noted that over 60% of the world's oil is transported by these tankers, and over 99% of that arrives safely without causing pollution. As to increase the efficiency in transportation (cost wise) of crude oil or refined products they are usually brought in ULCC or VLCC. A fully loaded VLCC will have a draft in excess of 20 meters. A ULCC can have a draft of as much as 25 meters. So, now the question arises what is a Draft?
The draft of a ship is the depth of a ship's bottom from the surface of the water. It is usually measured in meters. If the ship is full of heavy cargo, the draft will be greater than if it is not full. Heavy cargo will make the ship sink deeper in the water than light cargo. In other words, we can say that Draft determines the minimum depth of water a ship or boat can safely navigate. The draft can also be used to determine the weight of the cargo on board by calculating