Steve's Guide To Vessel Types.


The LNG carrier (Liquefied Natural Gas) and it's cousin the LPG carrier (Liquefied Petroleum Gas) are products of the late twentieth century. LNG and LPG are the preferred fuel types of certain countries for their industrial power needs. Japan is one such country that needs to import 95% of the LNG it needs, and so LNG has to be transported to Japan, but is not the easiest of cargoes to be transported. In its natural state, LNG is a gas, so to transport it, it needs to be kept as a liquefied state by reducing the temperature (simple application of Boyle's Law in physics !) down to a temperature of approximately MINUS 160 degrees C.

The shape of the "Moss Rosenberg" type of LNG Carrier is quite unmistakable, with the shape of the Moss tanks (which are like enormous spherical thermos flasks !) visible along the deck, which has led to the nickname of "Dinosaur Eggs Carriers". A similar concept is the "prismatic" type of LNG carrier, but instead of purely cylindrical tanks inside the vessel, they are "prismatically" shaped. An alternative design altogether is known as the "membrane" type, which allows for a more standard shape of vessel without the "eggs", but where the tanks are an integral part of the ship (and not independent from it). The newest and very largest of the LNG vessels are of this membrane type.

Obviously, the carriage of a potentially explosive substance - kept at very low temperatures in an unstable liquefied state - presents a very dangerous cargo, yet it is for this very fact, that LNG Carriers have about the best safety record of all maritime vessels. Only the best officers and crews are employed on these vessels, and the vessels themselves are maintained meticulously, and renewed frequently. There have been accidents involving LNG / LPG carriers, but where such events have occurred, the crews or salvors have so far, successfully managed to boil off the cargo into the atmosphere, thus rendering the dangerous cargo harmless.

To return to the Maritime Homepage CLICK HERE

This is an entirely non-commecial website providing information for general public educational interest purposes only.
If we have accidentally breached a copyright attaching to any of the facts or photographs appearing on this page,
and we shall remove the item immediately.

While great efforts have be made in trying to ensure the information given is accurate, the website creator shall take no responsibility for any errors nor be under any liability for any reliance put upon the information provided. Anyone seeking completely accurate information should visit commercial websites that seek to provide such information.