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Purpose and general use of Seagoing bulk carriers
Operation of sea going bulk carriers involved numerous hazards . Careful planning and exercising due caution for all critical shipboard matters are important . This site is a quick reference to international shipping community with guidance and information on the loading and discharging of various bulk cargo types and is to remain within the limitations as specified by the classification society.
It is vital to reduce the likelihood of over-stressing the ship's structure and also complying with all essential safety measures for a safe passage at sea. Our detail pages contain various bulk carrier related topics that might be useful for people working on board and those who working ashore in the terminal.
General features of seagoing bulk carriers
Bulk carriers are single-deck vessels, designed with top-side tanks and hopper side tanks in cargo spaces and are intended primarily to carry single-commodity solid bulk cargo.
Solid bulk cargo means any material, other than liquid or gas , consisting of a combination of particles , granules or any larger piece of material, generally uniform in composition, which is loaded directly into the cargo spaces of a ship without any immediate form of containment. Example of such dry cargo are grain, sugar and ores in bulk.
In its broadest sense, the term bulk carrier embraces all ships designed primarily for the carriage of solid or liquid cargo in bulk form, and so would include tankers. In ordinary usage, however, the term is normally used for those vessels designed for the transport of solid bulk cargos, typically grain and similar agricultural products, and mineral products like coal, ore, stone, etc., on one or more voyage legs.
What is a bulk carrier ?
"A ship which is intended primarily to carry dry cargo in bulk, including such types as ore carriers and combination carriers"
Fig : A Bulk carrier on sea passage
General features of bulk carriers are:
- Carrying capacity varying from 3,000 tonnes to 300,000 tonnes
- average speed of 12 ~ 15 knots
- single deck ships, ie no tweendecks
- small to medium sized bulk carriers (carrying capacity up to 40,000 tonnes) generally have cargo handling gear fitted, while larger vessels use shore based facilities for loading and unloading
- the cargo holds are usually large, without any obstructions, with larger hatch sizes to allow easy loading/unloading of cargoes
- most bulk carriers have one cargo hold dedicated as a ballast hold. This can be used on ballast voyages for improved stability. One or two further holds may be permitted for partially ballasting but only in port
- they have hydraulic, single pull or stacking (piggy- back) type steel hatch covers
- these ships usually have four types of ballast tanks :
sloping topside wing tanks
sloping bottom side wing tanks
double bottom tanks
fore peak and after peak ballast water tank.