Rise
floating crane
bulk
MACHINES of the
After years of being down in the doldrums the bulk industry seems to be climbing out of a black hole. With more investments made in cargo handling equipment, the floating crane market grabs a share of the action. Peter van Schie reports.
W
ith designs on the table for container cranes placed on pontoons to enhance the efficiency and productivity of loading and unloading containers from vessels, it seems that the container market is to follow in the footsteps of the bulk market in successfully deploying floating cranes for cargo handling.The concept of floating cranes for handling bulk is not new. In fact, floating cranes are used for cargo handling operations around the world. In Hong Kong they are being used for mid-stream operations, loading and unloading cargo from sea-going vessels on to barges. Currently, floating cranes are used in bulk terminals in both Rotterdam and Amsterdam with many bearing the familiar blue and yellow
‘trade-mark’ of former Dutch company, Figee. The company had a strong foothold in the floating crane market and encountered stiff competition from the Hungarian company Ganz Danubius. Combined with the slump in the bulk industry in the 90’s both Ganz and Figee saw their sales figures drop with Ganz Danubius diversifying its business activities to the shipbuilding industry and Figee going into liquidation.The company was split up and NKM Noell, the Netherlands, bought part of the company and also gained most of the engineers who had years of knowledge in designing specialised cranes.
Knowledge base Over the years, NKM Noell has concentrated on designing cranes for aluminium smelters, nuclear power plants, waste incineration plants, metallurgical plants and other industrial fields. “After a lull in investing in floating equipment for a number of years, investing in this type of equipment has started again,” says Mike Besyn, Sales Manager at NKM Noell.With the floating
crane know-how under their belt it is no surprise that NKM Noell is concentrating on this market segment and has already secured two orders. First and foremost bulk operator Ovet, with terminals in Terneuzen and Flushing, the Netherlands, has invested in a new floating crane of 40-tonnes grab capacity. Ovet is known to have always worked with 25-tonnes cranes but wanted to increase performance and capacity per crane, hence the higher capacity.The crane has to fit in the existing logistic concept of Ovet in Flushing and therefore has to work on a pontoon of only 21m wide.The Lemniscate type of NKM Noell special cranes has proven to be perfect for the new combination of capacity and pontoon width. “A second crane has been ordered by Amsterdam-based IGMA for unloading agri-bulk, minerals and biomass.This crane will be delivered in August this year,” Besyn adds.
Balancing act Another type of design that is being applied to floating grab cranes or loading platforms is
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and neglected with only 1 of the 10 original quays still in operation resulting in berthing waiting periods of up to several weeks.This expensive problem urged Seaboard to look for a suitable solution and after carefully reviewing all options (such as investing in the existing infrastructure, building a new quay), a floating trans-loading station proved to be the quickest, and most flexible and cost-effective solution. Recently, E-Crane was awarded a mega-contract for the CITIC (China) mining project in Australia.The contract included 3 floating trans-loading stations, each equipped with 2x 3000-Series E-Cranes capable of handling iron ore at Pilbara in northwest Australia. CITIC Pacific Mining expects to export 27.6 million tonnes per year.
that of equilibrium or balance crane. One company that is successfully applying this knowledge is Belgium-based Indusign trading under the well-known E-Crane brand (see article in December issue, page 25). Balance cranes are rapidly replacing the world’s aging fleet of conventional dock cranes as they are more productive and are cheaper to run and maintain.The design is based on an ingenious parallelogram style boom [almost similar to that of the Lemniscate type crane] and provides a direct mechanical connection between the counterweight and the load.This unique system ensures near perfect balance throughout its full working range. Another advantage of the balance crane over other floating crane concept is the fact that the counterweight moves not only up and down but also back and forward, resulting in a very small tipping moment.This means significantly higher stability: less barge movement, less friction between the floating terminal and the vessel, more precise and faster grab positioning, and greater comfort for the operator and the crew working on board of the floating station.As with any other floating crane, each E-Crane is built to customer specifications.Their latest order for a floating trans-loading station came from Midema (owned by Seaboard Corp), USA, for their
mother.The name reflects its duties, as it will be used to unload ships up to handy-max size (capacity 25 to 30.000 tonnes) and feed the
operations in Matadi in the Democratic Republic of Congo.The station consists of a 1000m2 barge, equipped with a 1500B-Series E-Crane with an outreach of 39.5m and lift capacity of 13.5 tonnes.The “Mama Mobokoli” was inaugurated late February in Zeebrugge, Belgium and will be towed to its final destination, across the Atlantic Ocean to Matadi. “Mama Mobokoli” is Lingala (one of Congo’s official languages) and translate as “the mother that takes care of you” - the nourishing/feeding
Midema (Minoterie de Matadi) flourmill.To unload the ships arriving at Midema, the Mama Mobokoli will be towed alongside the vessel that is to be discharged. Once secured, it uses its winches to move along the ship.This enables the E-Crane to unload all cargo holds quick and efficient. Matadi is the furthest inland harbour on the Congo River and, as in many African ports the users of this Congolese Port are confronted with major congestion problems.The existing infrastructure is dated
MHC technology The continuing interest from the market shows that there is still an important role in today’s bulk loading and unloading for the floating concept.A key strength of floating grab cranes is the fact that they work independently of the quay facilities. Peter Klein, Marketing Manager at Gottwald Port Technology, also underlined this point commenting that:“floating cranes operate when there is a lack of quays and solve quay congestion.” Gottwald’s floating cranes, like their portal harbour cranes, benefit from technology used in more than 1,100 Gottwald Mobile Harbour Cranes around the world. In fact, all three crane types mounted on barges, rails or rubber tyres are based on the same standardised concept and use the same assemblies from the slew ring up, thus offering the same performance. The floating crane concept is based on crane models manufactured according to a uniform design principle and sharing many common parts; subsequently adapted to waterway operation and combined with a customised barge. As the cranes are diesel-electrically driven, the diesel-generator set is installed in either the crane superstructure or on the barge. For full-electric operation an external landside power supply is being used. “Thanks to a high crane classification (A8 in grab operation) the cranes, in terms of their mechanical, structural and steel design, construction and condition, are designed for a significantly longer service life than cranes originally designed as a shipboard crane,” Klein states.This high classification also ensures a long service life for floating cranes subjected to additional forces, such as listing, trimming and waves. Three years after the initial launch of their floating crane concept [in 2004], Gottwald has received 12 orders, including two portal
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harbour cranes on a barge and a heavy-duty stevedoring crane for open-sea conditions. All cranes are intended for professional bulk handling and thus designed in the four-rope variant. One of Gottwald’s most recent orders came from St James Stevedoring Co.This specialist midstream operator on the lower Mississippi will augment its fleet for transloading imported bulk materials such as fertilizers and coal from sea-going vessels to barges with a third HPK 330 EG.The crane went into service at the end of last year. Another delivery in the fourth quarter of last year was for the first floating crane order from MMX Mineracao e Metálicos SA in the Port of Belem, Brazil.The two G HPK 7400 B cranes with a 50 tonnes grab curve will be deployed mid-stream in the port area of Belem and trans-load iron ore destined for export. “We have seen that an attractive low-cost solution for enhancing existing berths is floating crane operation alongside the quay wall. If the waterway is too shallow for sea-going vessels to moor directly alongside the quay, the floating crane can be positioned between quay and vessel and trans-load the cargo to land. Using floating cranes to bridge the gap between ship and quay means that investing in expensive deep quay walls and deep draught berths is no longer necessary. If an existing harbour basin needs to be dredged to a deeper level, no rehabilitation of the quay wall is required. Here, working with floating cranes is much less cost-intensive than the civil works required otherwise,” Klein explains. “One other interesting option for enhancing existing
bulk
berths is the use of floating crane operations alongside the quay wall or pier if there is insufficient quay structure for appropriate landside cranes. In this case the cargo can be trans-loaded directly from sea-going vessels to land (mainly by hopper), making landside cranes unnecessary,” Klein adds. “Again, cost intensive quay modifications can be avoided, but in this case Gottwald recommends using its portal harbour crane on barges. Each barge is fitted with rails on which the crane’s portal can travel.The crane can serve several ship holds, travelling between them on its rail-bound portal, preventing any warping to the barge or the ship.” Another Mobile Harbour Crane (MHC) manufacturer, Austrian-based Liebherr Werk Nenzing, who announced plans to apply the same MHC technology to its floating crane design – see article in March 2007 issue, page 35 – has declined to comment on their latest progress.The company planned a newly designed floating crane with Italian-based Logmarin. The design benefited from an unusual buffer storage on the barge, providing a greater ‘holding’ capacity than standard feeder river barges. Indications are that this new floating crane concept, based on Logmarin’s many years of experience in designing and operating floating cranes and MHC technology from Liebherr Werk Nenzing, has brought in some orders but that it is too early to report on the progress – so watch this space.
Conclusion So what is in store for floating grab cranes? In today’s port environment the floating crane will increase its importance due to the increased trade in the bulk market in general. The lemniscate type of floating crane (offered by E-Crane and NKM Noell) will have a bright future because of its unloading capacity per hour, its stability and expected lifetime. But it will continue to have increased competition from other manufacturers such as Gottwald Port Technology and Liebherr Werk Nenzing. Due to congestion in ports and the increase of trade, the steady increase in buying floating cargo handling equipment will continue in the coming decade, and in particular the traditional floating markets in Western Europe, especially in the Netherlands. According to Besyn, the loading ports in South America and Indonesia are likely to invest in more floating equipment. “Traditionally second hand equipment has been going from the Netherlands to the East and South,” he added. Bearing in mind that these ports have a lively trade in bulk cargoes, the purchases of new cargo handling equipment will be going from strength to strength.”
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