Dear Tony, Please find below answers of your querries --

Paralel conveyors? -Please note that the space on the jetties is always very tight,paralel conveyor means you will have to increase the width of jetty up to 5 m(min.) and the lenght may be 300 m(in the case of panamax vessel) so, all this extra cost has to be born by the client,there are other minus points if, you are going for paralel conveyors like--extra cost of mechanical equipment,maintenence,increase in the rail centre of the ship loader/unloader ect.

Overspeeding conveyors for a short time? -If the conveyor on the jetty is out of order,there is no question of overspeeding

Extra Frontend loaders and trucks to repalce a broken conveyor?

This can be a temporary arrangement but work- where loading and unloading capacities are very less.Please note that due to the shortage of vessels throughout the world, even a super cape vessel needs to be unloaded/loaded in a day.

Putting cranes to the side for repair, replacing it with an other crane??--This takes lot of time to bring a new/used crane to suit the existing arrangement.

Alternative routings of the conveyor belts?---This again depends upon the existing layout and very rarely done.

Anil Seth

Libran Engineering & Services,India

www.libranengineering.com ■

Tony M,

Greetings from my corner of the soon to be frozen eastern wilderness.

L.S.,

SPACE, SPACE, SPACE, MONEY, MONEY, MONEY!!!!!!!!!!!!!

That is what is at a premium at any loadout whether it is a jetty or a shore berth as Anil has said so eloquently.

cost is the faxtor X in any loading scenario. if it is possible and affordable to have redundant delivery systems it can be done but cost is allways the deciding factor and the value of the commodity and whether it is something that is time sensitive in nature-I.E. perishables, grain, sugars, seasonal consumer goods.

With any system breakdowns are a problem simply because it costs time and money-as shipping companies charge for time taken over the estimated or alotted time for loading as they are paid per trip.

loadouts do not accomidate trucks unless they are moving shipping containers and they always have cranes to use due to the nature of the product.

You should really look at an existing bulk loadout system to see what is involved as I stated previously in my postings to you. a good example is Canada Steam Ship linesas they ship a huge amount of bulk cargoes and you will learn everything you need to know from them regarding bulk materials handling for both onshore and off.

Another good example is grain elevators that are at shore berths,

If you look at them and how they operate you will see that a lot goes into the loading and unloading of bulk cargoes and how efficient they are simply because unless those ships are moving they are not making money for their owners and the commodity owners and brokers.

Loading most bulk commodities is done at an elevation higher than the vessel in question as rule to take advantage of gravity and its obvious benefit.

Iron ore loading on the great lakes is an excellent example as small ore jennies/railcars are used to move ore from the mines to the piers to reduce the weight on the piers and the iron ore berths have dump pockets where the cars are dumped with underbody doors and the iron ore is dropped into the ore carrier via a tilt out gravity chute or feeder depending on how old the pier is at a very high elevation in relation to the quay.

Unloading or loading is the problem as it relates to the port and its available equipment barges, tug boats, cranes, grabs, clamshell buckets, magnets for scrap iron, and of course human labor intensive unloading.

the big factor is tides, if the berth/quay is a sea berth or river berth feeding into the the ocean the water depth for secondary transport from the quay is also a deciding factor for all the above

hence loading into barges from the ship as they are docked next to each other .

there is no simple answer to your questions as I have stated previously as it is not simple or easy to do because every port is different

this also relates to the ports and thier machinery and its age and amount of useage and lack of maintenance. ■

"Terminals have to cope with a lot of failures, cranes out of order, ripped conveyor belts, and there are many other reasons why the whole terminal could be standing still."

These are all personnel issues. Cranes out of order - port soon out of business; ripped conveyor belt - sabotage/poor security. Providing bypasses & supplementary equipment will never solve such problems.

If the port equipment was correctly specified & built then the port should work as planned. Think about the ship. Out of order - it sinks!

There may be many other reasons why a terminal could be standing still - labour disputes, breakdown of hinterland infrastructure or court impounding of a berthed vessel. Such are outside the port designers brief & specification. Don't worry about such things any more than worry about the failure of the port to operate according to the specification!! ■

During my career in materials handling, since 1975, I only know of one company that uses parallel, 100% redundent conveyor systems at its plants.

The norm is to:

- buy quality systems and equipment

- keep adequate spares

- train your operators and maintenance personnel in condition monitoring and preventative maintenance

- schedule repairs that can wait (but don't wait too long)

- learn how to make emergency repairs quickly so operations may be resumed

Joe Dos Santos ■