Today‘s cargo volumes are more than many ports can handle with their present infrastructure. In some cases, the quays are approaching their capacity limits and can barely cope with the ever-increasing ship sizes.
However, for a number of terminal operators, the investment costs and the risks involved in expanding their present infrastructure are simply too high. A different solution is needed both to prevent cargo-handling bottlenecks and, at the same, provide a long-term flexible response to fluctuations in demand and longer-term market developments.
Gottwald floating cranes were developed as a solution to these challenges by Gottwald Port Technology, which has since become part of Terex Port Solutions, a business group within global equipment manufacturer Terex Corporation.
Of course, with floating cranes, there is no need for the purchase of additional land or the construction of new quays, involving lengthy approval procedures and time-consuming construction work.
Gottwald floating cranes, available as harbour pontoon cranes and portal harbour cranes on barges, are used:
Having the same technology incorporated in its mobile harbour cranes,Terex® Gottwald floating cranes offer the same strengths. Designed for all types of applications, they are available in all the different harbour crane variants.
Gottwald floating cranes are diesel-electrically driven and use electrical drive technology, it is also possible to make use of an external power source. If the crane works on the quay, it can be supplied with energy from the local power supply. Bypassing the diesel-powered generator increases the efficiency rating of the drive system and reduces maintenance costs. In both cases, operating costs are reduced while locally generated exhaust gases are also avoided.
The cranes’ electric drives, flexible choice of lifting gear, high lifting capacities and working speeds as well as service-friendly design provide efficiency, economy and a broad range of applications.
In its floating cranes, the company combines its crane know-how with the expertise of third-party barge manufacturers. The customer can choose between a used barge, which can be modified if necessary, and a new one.
They can either order the barge directly or appoint Terex Port Solutions to manage the whole project.
SHIP-TO-SHIP HANDLINGTerex
® Gottwald harbour pontoon cranes boost handling rates Terex® Gottwald floating cranes can be used on different types of waterways, including those having no or few quays. This is the case on the Mississippi in the USA, where, in the Port of South Louisiana,notfarfromNewOrleans,16Terex® Gottwald harbour pontoon cranes are employed in mid-stream operation.
These harbour pontoon cranes, all of which are 4-rope grab variants, tranship a wide range of bulk materials between ocean going vessels and river barges. As a result to the trend towards higher handling rates,Terex® Gottwald floating cranes over time have become larger as well. In demanding continuous-duty operation, currently they achieve handling rates of up to 1,850tph (tonnes per hour) depending on terminal and operating conditions.
For cargo-handling companies operating in the port, such as St. James Stevedoring Partners LLC, Associated Terminals LLC and ImpalaWarehouses LLC,Terex® Gottwald harbour pontoon cranes are the ideal solution for replacing old, lower- performance equipment and for boosting mid-stream handling rates.
SHIP-TO-SHORE HANDLINGTerex
® Gottwald harbour pontoon cranes offer unparalleled flexibility When space on the quay is limited,Terex® Gottwald harbour pontoon cranes can transfer the cargo direct from ship to shore, making land-based cranes unnecessary. Cost-intensive modification of the infrastructure can thus be avoided.
The cranes can also be used alongside existing handling equipment in order to share the workload at times of peak demand. And if a ship is unable to moor directly alongside the quaybecausethewateristooshallow,aTerex® Gottwald harbour pontoon crane can be used to bridge the gap between ship and quay, making it unnecessary to invest in expensive quay walls and deep-draught berths.
One of these cranes, a G HPK 8200 B variant, has been put to very flexible use in the Port of Amsterdam. It operates at the quayside, in mid-stream and in the waters beyond the locks. As a high-performance Generation 5 Terex® Gottwald harbour crane, it is used primarily for handling imported coal.
A COMBINATION OF EFFICIENCY AND FUNCTIONALITYPortal harbour cranes on barge
Terex
® Gottwald floating cranes were launched onto the market in 2004. Since then, 27 units have been put into service, including several portal harbour cranes on barges. Each barge is fitted with rails on which the crane‘s portal can travel. The crane can thus serve several ship holds, travelling between them on its rail-bound portal, making it unnecessary to warp the barge or the ship.
Two portal harbour cranes on barge are operated at the Shipyard River Terminal in Charleston, South Carolina, USA. They handle coal for local power stations and must meet the toughest flexibility requirements.
They operate at the pier, which is equipped with hoppers and conveyor belts for onward land transport of the coal.They can also be used mid-stream, transshipping coal from large ships to smaller barges, which, in turn, transport it on to its destination. These barge-mounted portal harbour cranes, which are of a 4-rope design, achieve handling rates of up to 1,100tph.
To keep the crane stable during travel on the barge, the rails are upwardly inclined from the centre to the two ends of the barge.
AswithallTerex® Gottwaldfloatingcranes,thebargeis supplied by a specialist manufacturer.
BULK HANDLING ON THE OPEN SEATerex
® Gottwald floating cranes up to 35km off the coast
In operation off the Indonesian coast, the Generation 5 floating cranes supplied so several customers are taking Terex
® Gottwald floating crane technology to new places. Used for open-sea transhipment of export coal from barges to ocean-going vessels up to several 10 kilometres off the coast, they are demonstrating their suitability for open-sea operation.
Such cranes can be operated in winds up to force 9 on the
Beaufort Scale and with waves up to 2.5 m high. The wind pressure and swell give rise to additional heeling moments along with increased motion of the crane. Gottwald Port Technology accounted for these severe conditions by modifying the design of the floating crane — including a reinforced boom design and an increased number of slewing gear drive units.
Sea Transport Logistics floating harbour transshipper
Sea Transport Logistics (STL) has a 36-year track record of bulk transshipper designs for remote areas and a variety of commodities.
In a bold move to improve the cost efficiency and environmental standards in remote area export of bulk materials, Sea Transport Logistics has addressed the key problems for export miners.
Until now bulk exporters in remote areas firstly had to acquire land closest to the export site and build expensive negative pressure storage sheds to hold at least one export shipload (180,000 tonnes).
Then a jetty has to be constructed to extend to at least 20m in depth to cater for Capesize (180,000dwt) bulkers.
This can be 3–10km long in shallow coastal areas. The mining company has to then place an Environmental Bond to remove the jetty and sheds at the end of the mine life. This is now relevant in many countries. This bond can cost approximately 30% of the initial jetty cost, and remains as a contingent liability for infrastructure owners
The cost of the sheds, jetty, loading equipment as shown, and removal bond can be up to US$1bn.
In a novel approach, Sea Transport Logistics proposes the construction of a small harbour with 4m depth at LAT closest to the mine. This harbour can be used for small feeder vessels, and given to the community at the end of the mine life.
Attached to the small harbour is a relatively small negative pressure storage shed (5–10,000 tonnes) with a wet dock for a small feeder vessel to reverse into. The feeder loads between 3–10,000 tonnes of ore and ships it to the transshipping vessel.
TRANSSHIPPER: TRADITIONAL1. dust problems and air pollution;
2. grab spillage and sea pollution;
3. open holds and rain/spray adversely affecting the transportable moisture limit (TML) and possibly delaying the departure;
4. a maximum constraining wave height of 2–2.5m; and
5. numbers 3 and/or 4 would cease the transshipment and demurrage costs commence.
FLOATING HARBOUR TRANSSHIPPERSResurrecting a 1988 Sea Transport Solutions concept of a Floating Harbour Transshipper (FHT), STL further developed and patented the FHT, which overcomes all the disadvantages of traditional systems.
The FHT comes in 4 relevant sizes:-
- Handysize FHT: 25–30,000 tonnes storage capacity 7m TPA;
- Panamax FHT: 40–50,000 tonnes storage capacity 12m TPA;
- Capesize FHT: 90–100,000 tonnes storage capacity 20m TPA;
- VLOC FHT: 200–240,000 tonnes storage capacity 35m TPA.
The small feeders then reverse into the wet dock of the FHT and the product is offloaded into the FHT or if the export vessel is alongside, the product goes directly into that vessel.
The FHT has minimal manning and no propulsion engines or large superstructures, and incorporates anchor ground tackle for the combination of both the FHT and the export vessel, or storm conditions for itself. It does have stern transverse Voith thrusters to keep the combination of the FHT and export vessel out of a beam sea wave vector, to avoid a synchronous rolling situation.
Load-out rate from the FHT is 3,500–6,000tph (tonnes per hour). This allows the feeder vessels to supplement the 40% of export cargo during the load cycle without incurring demurrage.
Each FHT comes with patented SLV feeder vessels. These shallow draught maximum payload, multi-screw vessels ensure minimization of dredging and have a degree of redundancy in case of engine gearbox or propeller breakages. The SLVs connect into the FHT by a three-axis connection coupling for a fast coupling that will endure heave, pitch and roll. The feeder can also fit in bow first to push the FHT to cyclone moorings or drydock. Alternatively the feeder can tow the FHT.
The FHT dock arrangement eliminates any stevedoring damage to feeder vessels and transshipment vessels and eliminates demurrage due to weather delays on the feeding operation.
Ten days of model tests were carried out at the Australian Maritime College during November 2010 confirming that five metre significant wave heights can be handled without stopping the feeder vessel operations, whereas 2–2.5 metres is the normal maximum limit. Motions coefficients have been established to readily verify the optimum size FHT and feeder for any particular coastal sea state anywhere in the world.
The FHT can also be used for other cargoes such as containers, possibly alleviating congestion of expanding container ports.
Mining companies in four continents are in dialogue with Sea Transport Logistics regarding this innovative system for bulk cargoes.
The Bulk FHT is an environmentally friendly solution for 21st century bulk cargo transhipments, with the following advantages:
ADVANTAGES FOR THE STATE, COMMUNITY AND ENVIRONMENT:- stockpile is at export site, downsizing or eliminating the need for large expensive negative pressure sheds ashore, and large jetties;y an environmentally superior system (smaller footprint, no dust, no spillage) than most other transfer systems and well clear of residential areas;
- shallower draught feeder vessels can be used from very small ports, at scheduled times, eliminating the need for dredging sensitive areas;
- revenue from mining royalties can be secured at an earlier time;
- lower road transport greenhouse gases with small harbours closer to the mine sites;
- employment and training opportunities in small ship feeder operations; and
- at completion of the mine life, a small harbour is available for community fishing and recreational boats.
ADVANTAGES FOR THE MINING COMPANYReducing capital expenditure and sovereign risk
- a solution that can be implemented quickly (as opposed to the lengthy wait of permits, etc.);
- stockpile is afloat and moveable, reducing the need for large storage sheds ashore;
- small shallow harbour eliminates the cost of a major jetty structure, and the bond for its removal at end of mine life, as the small harbour will be a legacy for the community or traditional owners; and
- an environmentally superior system (smaller footprint, no dust, no spillage) than most other transfer systems.
- Reducting operating expenditure
- can handle rougher seas, and eliminates demurrage and feeder stevedoring damage;
- lower power and manning requirements than traditional systems;
- reduced port charges — berthage, wharfage, tugs;
- faster transfer rates than conventional transshipper systems;
- and FHT with SLV feeders can handle inbound fuel, dangerous goods (such as ammonium nitrate) and outsized heavy lifts into mining areas with little or no infrastructure.