NEWS varying ground conditions into the underlying
bedrock, followed by reinforced concrete foundation beams, and the rail track. It will take just over four months to erect, test and commission the crane, for final handover in the summer of 2011, ensuring that the crane will be ready for its operational availability target of 1 September 2011. Te crane will be the largest in the UK, at a height of
68m to the underside of the main beams, with a span of 120m to cover the construction area of the new carriers at Rosyth. Te crane, which was selected on the basis of its safety, efficiency and cost, will liſt and place the carrier sub-blocks, and components includ- ing the upper blocks and sponsons, bow block, islands, and aircraſt liſts, without disrupting the dockside area adjacent to the ship. Te crane’s 1000tonne liſting capacity is provided by
three hooks. Te individual capacity of each provides a valuable degree of flexibility in liſting some awkward loads with difficult centres of gravity, and allows units or blocks to be turned over, up to a unit load of 500tonnes. Two of the hooks are suspended from an upper trolley (each hook having a 300tonne capacity) and one from a central, lower, trolley with a 500tonne capacity. While the three hooks have a greater cumula- tive liſting capacity than 1000tonnes, the total capacity is defined by the crane structure. Te arrival of the crane also marks the first use of the
newly widened direct entrance. Rosyth has the largest non-tidal basin for ship repair in the UK, separated from the Firth of Forth by a sliding gate entrance to hold the water back. Tis has been widened by 4m to over 42m (removing 8m on one side, and adding 4m to the other) to allow entry of the blocks from the various dockyards where they are being built, departure of the completed vessel, and return for maintenance, in a grand civil engineering project. To undertake the direct entrance works, two
massive cofferdams were constructed, one on the main basin side and one on the Forth estuary side, to create a dry working space. Tis included sheet piling to bedrock, and placing large semi-circular steel
box section beams and reinforced concrete beams constructed underwater and below seabed level. Tis was followed by a staged excavation to bedrock at a depth of 20m below sea level, on the north side where a new wall was constructed. Construction of the foundation for this wall alone involved 5750tonnes of mass concrete placed in one continuous pour. Te construction of the direct entrance has taken around 18 months, and involved around 110 workers. It followed successful completion of Number 1 Dock where final assembly and integration of the carriers will take place.
Equipment & technology Rolls-Royce wins
RAS contract Rolls-Royce has been selected to supply a unique replen- ishment-at-sea (RAS) system to the UK Royal Navy that will enable heavier-than-ever loads to be transferred between ships. Rolls-Royce has already completed the detailed design
phase of the project. The latest contract, worth £25 million (US$40.6 million), includes the construction of a land-based demonstrator to trial the new equipment. Commodore Preston, Head of Afloat Support at
the Ministry of Defence’s Defence Equipment and Support organisation, said: “We are delighted that the contract for this vital training facility has been signed. This equipment will help train Royal Navy and Royal Fleet Auxiliary crews in real-time operational scenarios in a safe and controlled environment before undertaking it at sea.” Te demonstrator will be built at the Royal Navy’s
training facility at HMS Raleigh, near Plymouth. It will be used to train operators of all Royal Navy surface ships in a realistic operating environment.
Propulsion Wärtsilä introduces
new waterjet Wärtsilä has introduced a new series of waterjets. Te new midsize series enhances Wärtsilä’s competitive range of stainless steel jets to include all sizes from 510mm to 3250mm. Te new series is aimed particu- larly at the high-speed ferry, high-speed patrol craſt, and customized yachting segments. The new, high-performance waterjets have a
The huge crane will be used to assemble the Royal Navy’s new Queen Elizabeth aircraft carriers.
10
number of competitive advantages and are designed for long-term, reliable performance. Tis is achieved through the use of high-quality materials for structural parts, and the wide use of stainless steel in the jet construction. Although aluminium is a widely used and accepted material for jet fabrication, the Wärtsilä
Warship Technology May 2011
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40