W.J.D. Piet
Ro-ro freight shipping. Current situation and developments
Literature survey,
Report 2005.TL.6995, Transport Engineering and Logistics.
The purpose of this thesis is to give an overview of the transportation of
freight over sea by means of a Roll-on / Roll-off loading method. Ro-Ro
is a loading method that in terms of transported tonnage is a small player in
the market of the transportation of freight overseas. For certain types of
goods and trade routes it is still a competitive player in the market of
transporting goods overseas.
Ro-Ro is merely a term for the manor in which the ship is loaded. It is
possible that different types of goods can be transported more efficiently
in specialized types of ships. In this paper an overview is given of the
different types of ships and the alterations to the design of the vessels
are given.
The planning and designing of a dedicated Ro-Ro terminal is explained, and
with the planning/designing of a Ro-Ro terminal an overview is given of the
different types of Cargo Handling Equipment and when to use certain
equipment.
Furthermore this thesis mentions the developments in Ro-Ro freight
transportation in terms of new Ro-Ro vessel designs and new developments of
Ro-Ro transhipment methods.
The found information is used to comment on two Ro-Ro case studies in the
end of the thesis. The first case is about the possibility of a newly to be
implemented Ro-Ro trade network on the Lake Superior between Canada and the
U.S.A. and the second case is the design of a Ro-Ro terminal in the UK by
the Posford Duvivier company.
Summary
Due to globalization the amount of goods that need to be transported from
one place to another keeps increasing much more than you should expect based
on the growth of the population. Large vessels travel from China to Europe,
packed with containers to deliver the goods which are produced in China and
bought be Europeans. In the market of nonbulk goods the Lift-On/Lift-Off
(Lo-Lo) loading method on a cellular vessel is dominant. A crane is used to
lift the container from the ground to the ship during the loading of a
vessel and the container is lifted from the vessel to the ground by means of
the same crane, which is the Lo-Lo method.
The loading of a vessel can also be done by rolling the cargo onboard a
vessel. This can be achieved with cargo which from itself is equipped with
wheels, like cars or trucks, or by with wheeled equipment which is able to
carry the cargo onboard a vessel. A Rollon/ Roll-off (Ro-Ro) vessel is
equipped one or more loading decks which can be accessed by one or more
ramps at the quay side or by means of an onboard ramp or elevator.
All in all a Ro-Ro vessel is less space efficient when compared to a Lo-Lo
vessel and mostly due to this reason Ro-Ro is a more expensive method of
cargo handling. This can be countered by introducing dedicated Ro-Ro
vessels, like for instance Pure Car Truck Carriers, trailer ships for either
transport accompanied by a driver of unaccompanied, Ro-Ro vessels for the
transport of forest products, rail ferries for the transport of rail wagons
or even complete trains and Ro-Ro/Passenger (Ro/Pax) vessels.
In the design of a vessel the optimal height of the decks can vary. A Pure Car
Carrier for instance or a trailer vessel requires less height per deck than for
instance double container stacked MAFI-trailers. It is optional to implement
hoistable decks in the design of a Ro-Ro vessel in order to vary the deck
height so a mixed combination of cargo can be stored more efficiently.
Due to the variety in Ro-Ro cargo there is a variety in lashing methods
onboard the vessel in to prevent the shifting of cargo. Since in principle
Ro-Ro cargo is wheeled blocking its movement is important. This can be
simplified by using a Sto-Ro method (Stow and Roll), since then the cargo
only has to be supported instead of secured. This can be done by means of
wooden structures, air cushions, units or nets.
When compared with the commonly used Lo-Lo method, Ro-Ro has its pros and its
cons.
- Ro-Ro for instance is able to handle and store heavy cargo, whereas a
container has its limitations;
- Accompanied transport is possible and therefore the cargo can have a
higher security;
- A Ro-Ro terminal has lower initial investment costs whereas a Lo-Lo
vessel has a lower vessel investment cost;
- A Ro-Ro vessel can be loaded and unloaded more quickly and therefore
spent time in port;
- When comparing transport cost, trailers are more expensive to transport
than containers;
- Less chance of cargo damage with a Ro-Ro method.
When planning and designing a Ro-Ro terminal the first thing to do is
estimate the total annual cargo throughput. Is the terminal economically
viable? The Ro-Ro cargo has to be split into types of Ro-Ro cargo volume.
With a high volume of a certain type of Ro-Ro cargo, it can be economically
viable to dedicate the terminal to a single type of cargo. Furthermore the
location can be varied as well as the lay-out of the berthing area. A type
of land connection has to be chosen which depends on local conditions, like
tidal variations, or vessels type, like for instance single, double ore more
deck-vessels.
In general Ro-Ro cargo cannot be stacked. Therefore a short
stay on terminal is critical to limit the costs of transporting with a Ro-Ro
method. Is a Ro-Ro terminal dedicated to a single type of Ro-Ro good, it is
an option to have dedicated cargo handling equipment on site of the
terminal. In general dedicated equipment is more expensive in terms of
initial investment, but its efficiency is higher.
The tendency in Ro-Ro shipping is offering flexibility. It is not unthinkable
that containers are being moved from A to B, but return cargo is of another
type. Containers are being mixed with bulk, cars, cassettes and other types. An
all-in-one vessel has been designed to be able to handle mixed types of cargo.
The hybrid freight Ro-Ro has been designed based on a similar concept. In this
case it combines Ro-Ro decks with cellular container capacity.
In the European Union the Marco Polo program has been set up to seek other
means of transportation in order to offset some of the disadvantages of road
transportation. In general transportation over water is less polluting per
tonnage than transportation of water. The European High Speed Cargo Vessel
has been developed in order to give a solution for the growing transport of
goods, with other methods than road transportation. The fastship concept has
been set up with similar reasons, to provide another alternative
transportation method.
The IPSI and INTEGRATION projects have been set up in order to improve the
Ro-Ro chain. An optimal system of automation on the terminal side and the ship
side and automating the lashing process onboard the vessel.
The concept "intermodeship" had been developed to achieve a higher
onboard-storage efficiency. Ro-Ro cannot be stacked, but by using onboard lifts
an optimal loading efficiency can be achieved.
On the connection with the hinterland the main disadvantage is the
incompatibility of RoRo equipment with other modes of transportation.
Specialized rail wagons for lifting swap bodies and cassettes have been
developed. The commonly used cassette is too wide for road and rail
transportation. Therefore a new cassette had been developed which is less
wide in order to be compatible with rail and road transportation. This is
called the wheelless system.
A rollerbarge has been introduced in order to be able to load large blocks of
containers at once in order to reduce to time in port.
At the end two case studies have been discussed in order to provide a link
between information found in literature and choices made in a case study. Two
different angles have been reviewed; the "Lake Superior" case handles the
possibility of creating a complete new network of Ro-Ro terminal along side the
lake and the "UK" case study by Posford Duvivier handles the development of a
single terminal.
Reports on Transport Engineering and Logistics (in Dutch)
Modified: 2006.05.23;
logistics@3mE.tudelft.nl
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