Where ships go to die

At the end of their working lives, the large ships can be broken up. This can be done by beaching large ships and using welding torches to cut the steel. This steel can then be recycled by adding into BOS vessel in steelmaking (to recover heat) or melted using any kind of furnace.

This video shows a ship being beached at Gadani Pakistan:

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Ship bending due to wave motion

Modern container ships are made from welded steel plates and can have length of up to almost 400 m. They carry huge numbers of inter-modal containers (which can also be carried by truck or train).

The first container ships were converted world war 2 T2 tankers typically 152.9 m in total length and 20.7 m in width (beam). The largest container vessel today is MSC Oscar, 395.4 m in length and 59 m wide and capable of carrying 19224 containers (TEU — twenty foot equivalent unit).

As these ships travel the globe they are bashed by waves, in this video we can see the displacements this causes inside the vessel.

Video shows the container ship MSC Busan in heavy seas. In the video at around 11 s a wave of height approx. 7-8 meters hits the vessel.

More links

https://bainite.wordpress.com/2013/06/23/mol-comfort-shipwreck/

http://www.bbc.co.uk/news/uk-england-suffolk-30700269

Biggest Ship ever

The largest ship to date is was the Seawise Giant built by Sumitomo Heavy Industries at Oppama shipyard. A ship so big that it takes Top Gear presenter Jeremy Clarkson to describe it.

http://en.wikipedia.org/wiki/Seawise_Giant

Seawise Giant had several names since it’s building from 1974-1979 and it’s scrapping in 2009, including Knock Nevis. Here is a comparison between some of the other largest ships in the world.

The largest ships so far.

Seawise Giant was the longest ship ever constructed, longer than the height of many of the world’s tallest buildings, larger than the Petronas Twin Towers at 451.9 m (1,483 ft). In December 2013 Prelude FLNG became the longest ship ever constucted which measures 488 m (1,601 ft), built by Samsung Heavy Industries at Geoje Shipyard. Also four Batillus-class supertankers operated from 1976-2003 built at the Chantiers de l’Atlantique shipyards in France which had a larger gross tonnage.

The Pentagon, 431 m
RMS Queen Mary 2, 345 m, USS Enterprise (CVN-65), 342 m, Hindenburg, 245 m, Yamato, 263 m, Empire State Building, 443 m, Knock Nevis, ex-Seawise Giant, 458 m

MOL Comfort shipwreck

On 17th June MOL (Mitsui O.S.K. Lines) Comfort cracked mid-ship and broke into two pieces while carrying 4832 containers from Singapore to Jeddah. The incident occurred 230 miles off the coast of Somalia in a swell of 5-8 m. The ship was built by MHI at Nagasaki and completed in July 2008. It operated as APL (America President Lines) Russia until 1st June 2012. As of 23rd June most of containers are still aboard, and tugs are on route to try to salvage the two sections and remaining cargo.

MOL Comfort is a large post-panamax container ship, one of 12 ships built of similar design, which were the first classified by Nippon Kaiji Kyokai to utilise high strength steel with yield point of 470 MPa in the hull structure.

As pointed out at gcaptain.com http://gcaptain.com/comfort-container-weight-issue/, the MOL Comfort was built at a top quality shipyard and operated by a tip-top liner company. The things that come to mind immediately are 1) Weather 2) Welding quality 3) Pirates?, gcaptain suggests tehre may also be an effect from the undeclared weight of containers. This is an interesting problem, since surely the total weight of the ship is easy to measure by measuring the displacement in dock? Also easy to weigh each container as the loading cranes can easily be fitted with equipment to weigh the loads (they need this anyway to ensure safety of the crane). It seems common practice to misreport container weights during loading, but are these weight then used to decide the position of the containers on board? Containers need to be placed, and moved, in such a way as to minimise the forces on the hull at all times.

Mol Comfort Shipwreack

Lloyd’s Register marine director and chairman of the International Association of Classification Societies Tom Boardley said:

This incident is of great concern and we want to know the cause of this structural failure.

Mol Comfort Breaks in Two

MOL press releases regarding the MOL Comfort can currently be found here:
http://www.mol.co.jp/en/pr/2013/index.html

Ths ships builders MHI have set up a task force to work with MOL to investigate the source of the failure.
MHI press releases regarding the MOL Comfort can currently be found here:
http://www.mhi.co.jp/en/notice/index.html

As of 24 June the two halves are still floating and can be found drifting near 15”12N 66’53”E and 13’38”N 64’10”E. Original location was 12’30″N 60’E.

As of 25 June two MHI engineers are in place on one of the tugs sent to salvage the container ship, to investigate the cause(s). There are no statements from the crew, who may also be able to shed light on the incident.

Addendum

The aft part of the ship eventually sunk with the containers at at 16:48 JST (11:48 Dubai time) on June 27. The fore part is being towed towards the Arabian Gulf.

Although the ships are built following international standards, the sister ships will subsequently be strengthened to at least twice the standard strength.