Future Crane Evolution and Ship-Barge Container Transfers

By Harry Valentine 2012-11-20 15:11:00

Written by Harry Valentine

The economics of international trade demands that transportation planners and researchers continually seek methods by which to improve the productivity, efficiency and cost competitiveness of freight transport. These methods have included several developments in intermodal transportation technology and also in the design of intermodal terminals. In some jurisdictions, trucks will carry 2 or 3 containers on trailers that travel along designated motorways. Several railways carry double-stacked containers aboard extended length trains that are propelled multiple locomotives.

Traffic Congestion:

Traffic congestion occurs roadways located near major intermodal terminals, even affecting terminal operations. Many main railway lines are operating near design capacity, while the recent introduction of larger container ships has prompted some ports to operate only marine-railway intermodal transfers. The alternative involves hundreds of trucks causing traffic gridlock on roadways that connect to main intermodal terminals.

Inland Waterways:

Recent developments in river transport enhance both the efficiency and cost-competitiveness of barge transportation. Advances in coupled barge train technology allow barge-trains to be pushed and steered from the stern, like a conventional marine craft. Barge trains interline with oceanic ships at several international ports and are becoming a cost competitive in intermodal link to inland locations, along main routes where they compete against trucks and trains. Container-on-barge operations are becoming a viable option along such rivers such as the Mississippi (USA), the Danube (Europe), the Parana (South America) and the Yangtze (China).

Cranes:

At the present time at ship-barge terminals, each crane can only transfer one container at a time between ship and barge. There is a perceived need to develop a crane technology that can transfer multiple containers between ships and barges in a single movement. Such technology may evolve from precedents in maritime transport and other areas related to transportation and the transfer of heavy loads.

Precedents:

Advances in telecommunications technology allow doctors to perform operations from distant and remote locations. The same technology may be applied to various aspects of the transportations sector, including the operation of navigation locks and also of cranes. Future crane operators may program or direct computer automated crane machines to improve the efficiency of production and decrease the unloading and loading duration of ships and barges. The precedent of lift-bridges that are built over rivers may be adapted to future crane designs.

These bridges are either of the box girder or of the cantilever truss design, both of which carry railway lines across rivers and valleys. The overhead suspension railway system that operates in Wuppertal in Germany contains proven precedent that may be adapted to future crane design. The design of navigation locks that allow watercraft to change elevation may be adapted to future intermodal operations. The combination of these technologies offers a method by which to greatly enhance ship-barge transfer of containers.

Future Ship-Barge Transfers:

A future ship-barge intermodal terminal would include parallel navigation lock-type docks that are constructed like bridge piers. An oceanic container ship and a barge train would moor between these dock-piers that would support the weight of cranes that would move on rails built along the dock-piers. Between 2 and 3-vertical cantilever-truss structures would carry a cantilever cross member that would straddle over the barge and the ship, possibly over dock-piers outside the watercraft. 

The cantilever cross member would carry a transverse carriage and several sub-carriages. Automated computer control would direct the movements of carriage and sub-carriages that would simultaneous move multiple containers in a single transfer, reducing ship-barge dwell time at the terminal. At the Port of New Orleans, each barge of the Mississippi barge train is built to a length to 200-ft a beam of 35-ft and able to carry containers 4-abreast.

Barges coupled 2-abreast to a combined beam of 70-ft can would carry 2-groups of 4-abreat containers, for an overall 8-abreast layout. The crane’s automated carriage operation may transfer up to 8-containers in a single movement between ship and barge. The computer programming may allow carriages to pick up containers from or deliver them to different elevations along the same row.

Pre-Sorting Containers:

While some barge trains would carry all containers between an inland and ocean port, other barge trains would serve multiple ports on the same route. In the latter operation, barges would be coupled to and uncoupled from the barge train. When a barge train loaded with containers arrives at an oceanic port, computers would control the transfer of containers to the oceanic ship. If the oceanic ship is headed to a port where the containers would be transferred on to barge trains, containers may be loaded in a pre-determined sequence based on final destination.

While the automated cranes would transfer some containers directly from barge to ship, they would divert other containers on to conveyors. Companion automated cranes controlled by the same computer and located at other points along the ship, would load the containers at pre-designated locations aboard the ship. Upon arrival at the port of destination, operations personnel would know the arrangement of containers on deck, as well as the inland port of destination for each group of containers.

Computers that operate the cranes would contain that information and rapidly transfer containers to the appropriate barge(s) destined for a particular inland port. A ship may arrive at a ship-barge port with containers loaded at random. The automated cranes would transfer some containers directly from ship to barge train and divert other containers to the conveyor system. Companion automated cranes at other points along the ship would transfer the containers from the conveyors to the appropriate barges.

While some barge trains may sail inland to a single inland port, other barge trains will stop to uncouple a barge destined for a smaller inland port. A future automated crane technology would enhance ship-barge intermodal operations, reducing time duration at port and enhancing the economics of container-on-barge operations along inland waterways. Barge trains have the potential to operate at lower cost per container than railways or trucks.

Security:

National Customs agencies have a mandate to inspect good that enter into their jurisdictions. There may be scope to include scanning technology into automated crane carriages that inspect the contents of shipping containers upon arrival. Authorities may intercept suspicious containers at inland ports so as to maintain the efficiency of the transportation system. They may divert highly suspicious containers upon arrival at the main port.

About the Author
Mr. Valentine holds a degree in mechanical engineering from Carleton University, Ottawa, Canada, with specialization in thermodynamics (energy conversion) and transportation technology.

He served as a research assistant to Dr Ata Khan, professor of transportation engineering who is still on staff at Carleton University.  Mr. Valentine has a background in free-market economics and has worked as a technical journalist for the past 10-years in the energy and transportation industries.

Over a period of 20 years he has undertaken extensive research, authored and published numerous technical articles in the field of transportation energy.  His economics commentaries have included several articles on issues that pertain to electric power generation.

Mr. Valentine has technical journalistic experience covering low-grade and high-grade geothermal energy, steam generators (with continuous blow down to keep the boiler water clean), engine exhausts, solar thermal (low-grade and low-grade thermal), nuclear and coal-fired thermal steam-power stations.

He can be reached at harrycv@hotmail.com.

MarEx does not necessarily endorse any opinions herein.

Related Articles:

OP-ED: Marine Propulsive Efficiency in Speed Restricted Waterways

OP-ED: Prospects For a Trans-Arctic Barge Canal Across Canada

OP-ED: Ballast Water and Barge Trains on the St Lawrence Seaway

The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.