Ship crane
A ship crane is a ship's own loading gear .
General development
From the 1970s onwards, ship cranes gradually replaced the loading boom . When in the first few years the lifting capacity ( SWL , English safe working load ) was still modest (5–10 tons ), they could not lift more than cargo booms. However, they were easier to use and the tedious task of loading and unloading was considerably simplified.
In the 1980s / 1990s, the ship cranes started to develop, which reached a temporary high point with the delivery of two heavy lift ships built at the Sietas shipyard in late 2010 and early 2011 for the Altes Land shipping office . These ships were equipped with two cranes from Neuenfelder Maschinenfabrik with a SWL of 1000 mt each.
Construction
Most of the cranes are tower cranes . They consist of the foundation that supports the slewing ring with the tower on top. With this design, all machines, winches, etc. are installed above the slewing ring in the tower so that the crane can rotate 360 ° without limitation. However, it also means that the center of gravity of these cranes is quite high. This in turn has negative effects on the stability of the ship.
Another construction method, which is only used for heavy lift cranes , is practiced by the Dutch company Huisman-Itrec . These so-called mast cranes consist of a fixed, massive mast, on the lower third of which a turntable runs around the outside of the mast, to which the boom is attached. The machines and winches are installed under the mast near the waterline. This keeps the crane's center of gravity low. However, it has the disadvantage that the cable guide at the top of the mast prevents these cranes from rotating indefinitely.
The ships with mast cranes can easily drive with topped booms; this is only possible to a limited extent with tower crane cranes.
Heavy lift cranes
Heavy lift cranes are usually referred to as cranes that can lift more than 80 tons. They are much slower than smaller cranes and are therefore often equipped with an auxiliary hoist, which allows them to handle lighter loads more quickly and is an aid to the crew when attaching lifting gear.
Cranes for handling containers and general cargo
Cranes for handling containers and general cargo or bulk goods usually have a SWL of less than 80 tons. Many small and medium-sized container ships have 45-tonne cranes that are used for handling containers in ports that do not have the necessary equipment ( container cranes , mobile harbor cranes, etc.) for container handling. In the beginning, container ships in areas with little infrastructure were also equipped with gantry cranes that could be moved on deck, as this allows containers to be handled more quickly.
Mostly smaller, but several cranes (one for each hatch) are installed on bulk carriers , which can usually lift around 30 tons.
Manufacturer
Neuenfelder Maschinenfabrik ( TTS-NMF ) builds ship cranes with a lifting capacity of 5 to 1000 tons SWL and is therefore a leader in the construction of heavy lift cranes. In addition, provide more Liebherr ago, MacGregor and other ship cranes. Huisman-Itrec and Liebherr are the only manufacturers to build mast cranes.
See also
Web links
literature
- Frank Brunecker (Ed.): Liebherr - Cranes + more. Exhibition catalog. Museum Biberach, City of Biberach 2005.