Know A Ship - RoRo Ships- Part One

Ro-ro is an acronym for Roll-on/roll-off.Roll-on/roll-off ships are vessels that are used to carry wheeled cargo.The cargo could be anything from your car or private helicopter to a train carriage antique like the dining car of "The Orient Express".Today this vessel has grown from its humble origins of that of a Train Ferry to the New MV Tønsberg, the largest car/truck carrier, a video of the same has been included below this section.

RO-RO VESSELS HOW AND WHY?

It is not just size that determines how these vessels have evolved through the years to fit certain standards and practices but other factors play a crucial role too as although automobiles are highly traded commodities,cargo of other kinds are also sometimes taken along-with on board.This introduces certain variations in design and corresponding structural characteristics.

The cargo-carrying section of the ship is a large open deck with a loading ramp usually at the aft end or bow or sometimes both ends to facilitate faster loading/unloading process.The cargo may be driven aboard under its own power or loaded by carriers with straddles or fork lift trucks.

Here is picture of a Ro-ro vessel with a bow ramp and door.

  

  And Here is one with a stern ramp and door.

A SLICE OF HISTORY:                                                                                                                          The first ships of this type were the Ferry, equipped with railways to allow the transport of train carriages between the margins of the rivers that were too wide for bridges.One of the first ferry ships,the Forfarshire was built in 1861.

The use of the Ro-ro concept in merchant ships started in the late 1940’s, early 1950’s, mainly in short-sea routes.

Today,these vessels contribute to many sea going trade purposes and military operations.They are even being considered on being introduced in the luxury market currently dominated by cruise liners and yachts.

FIT FOR PURPOSE:

Today,we have many variations or hybrid versions of these ships,among them the prominent ones are 

• ROPAX  (roll-on/roll-off + passenger)
• ConRO   (hybrid of a RORO and a container ship.)
• LMSR     (Large, Medium-Speed Roll-on/Roll-off )
• RoLo       (roll-on/lift-off)

And The Like,there are other similar variations but all depends upon the requirements of the client for which the vessel caters to. 

Military Ro-ro vessels exist specifically to transport military cargo called Military(MSC-Type Ro-ro vessels).

The ship has also proved extremely popular with holiday makers and private car owners. It has significantly contributed to the growth of tourism. A person can take his car from one country to another by sea with the help of a ro-ro vessel.

Next time,we shall be discussing about the internal characteristics of a Ro-ro vessel,and some features of a Lo-Lo vessel shall be discussed.

Do not forget to watch this video about the world's largest Ro-ro vessel ,The MV Tønsberg. LSD

 For Part-Two click on the following link http://lshipdesign.blogspot.com/ .

Article By: Sudripto Khasnabis

Author's Note: This article is the first one about Roll-on/Roll-off  Vessels.The next article will contain some more information on these kind of vessels and some study of another vessel which has some similar features and working techniques,the Lo-Lo Ships.The section shall proceed regularly with similar articles about other ship types with a common aim of making the reader aware of the general principles on which their design and construction is based and their utility and characteristics. The videos and the figure do not belong to LSD, and full credit for the same goes to their respective owners. If you have any queries or doubts,do not forget to write to me at  learnshipdesign@gmail.com