Today, the transport system around the world is significantly distributed between different modes of transport. Any thing that comes to us from abroad is delivered by road, rail, air or sea transport. The role of the latter is especially great in connecting continents and continents, since water covers most of the earth's surface, which makes transportation by trucks and trains impossible. Air travel is too expensive. Moreover, the aircraft is capable of carrying not so much weight. There remains one type of transport that has been in demand for hundreds of years - marine.
In view of how much trade relations have developed to date, many types of ships have begun to be used in practice. For example, there are dry cargo vessels (including multi-purpose ships, bulk carriers, lighter carriers), refrigerators (vessels with refrigeration equipment for transporting products), container ships (for transporting classic 8-foot sea containers) and others. At these vessels, the deadweight is adapted to transport a certain type of product; they are all equipped with special equipment. Thus, almost any product can be transported by sea anywhere in sufficient quantities!
How are ships applied?
Most goods shipped in bulk are shipped by sea. A ship is capable of accommodating thousands of tons of cargo - not a single aircraft in the world can lift so much. What is also important is the relatively low cost of transporting large shipments by sea. For comparison, if the largest An-225 aircraft (Mriya) is capable of transporting 120 tons, then the deadweight of the vessel (this is the gross tonnage) of even a small ship is 3-5 thousand tons. What to say about large floating platforms for transportation. Now it’s obvious that the use of water transport is much more rational when it comes to the transport of goods. The drawback of the ships can only be called the longer duration of their voyages. However, this is not scary, because you can plan the delivery of goods, counting the time for delivery by sea.
How much can a ship accommodate?
As already noted, the capacity of the ship is characterized by such an indicator as the deadweight of the vessel. This designation came from the English deadweight, which means "dead weight". It is understood that it is precisely such a maximum mass that the vessel capable of moving at normal speed is capable of transporting. It is impossible to exceed this indicator. It is important to know it in order to effectively charter a ship, without forcing it to sail with empty seats and not to overload to a critical mass. For ships, the deadweight is calculated by taking the mass of the empty ship ready for departure from the mass at which the ship is completely immersed in water to the cargo mark (full displacement).
What does this characteristic mean?
In fact, the ship’s deadweight is the mass difference that is not enough to fully load the ship, minus the basic equipment of the ship. When loading, this characteristic is taken into account in such a way as the extreme value, the maximum that the vessel can carry. Transport companies, chartering sea ships and engaged in transportation on a regular basis, knowing that the deadweight of the ship is its most important characteristic, are able to distribute cargoes as efficiently as possible on free ships. This value can also be called the carrying capacity of a single floating vessel.
Why do you need to calculate the deadweight?
In addition to knowing how much weight can be transported as much as possible on a particular ship, with the help of deadweight it is also possible to efficiently calculate the mass of “payload” and the cargo that is necessary for sailing. The first can include those goods and things that, according to the contract, the ship should transport from point A to point B. As for the second, cargo for navigation, it should include reserves of
fresh water, fuel and other combustible materials, reserves provisions, as well as the weight of all people on board the vessel.
According to maritime experts, the deadweight of a ship is usually two parts, distributed in the ratio of 90% to 10% in favor of the so-called payload.
Deadweight examples of various vessels
In order to more clearly represent the size of this quantity, we consider some examples. So, there is a bulk carrier "Omsk", which belongs to the class R2 / R3 RSN. This is a ship with a body length of 108 and a width of 15 meters. This ship is propelled by two propellers. According to data from the Maritime Register of Shipping, the deadweight of the Omsky vessel is 3070 tons both when moving along the river and by sea. It turns out that about 200 tons will make up reserve stocks and almost 2800 tons can be placed on this ship in the form of cargo. It should be noted that the dry cargo ship will have a ratio of 90% to 10%, and somewhere around 95% to 5% - more in favor of containing cargo than on passenger ships.
Other ship features
Obviously, such a characteristic as a ship’s deadweight is an important parameter, which is extremely necessary when calculating the efficiency of a ship’s expedition and its final cost. However, it is obvious that this is not the only such important indicator. For example, when chartering a floating vessel, you should also pay attention to the total capacity of the holds, their sizes. In addition, the type of cargo ship, its intended purpose (for the transport of which goods it is used primarily) plays an important role.
On the whole, such an indicator as carrying capacity plays a huge role. Organizers of transportation have to deal with it every time a ship is loaded.