Professional Skipper Magazine from VIP Publications

S93 May-Jun 2013 with NZ Aquaculture

The only specialised marine publication in Oceania that focuses on the maritime industry, from super yachts to small craft to large commercial ships, including coastal shipping, tugs, tow boats, barges, ferries, tourist, sport-fishing craft

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The hopper barge opens like an inverted clam The hydraulic power pack the locking pins release to open the clamshell barge, there is no holding back. It takes about 10-15 seconds for the barge to empty and pop up. To close and bring the hulls together takes around a further four to five minutes during which time the hopper is flushed before the locking pins engage once again sealing the barge. Once the green lights register that the pins are safely re-engaged and the barge locked close, the hydraulics and motor may be shut down and the trip home begins. This takes about 10 hours depending on the weather. In observing the tow when leaving the marina, we note the barge appears to be a bit lively on a short 50m tow, necessitating the use of a second smaller towboat for both close quarters control and safety. Once clear of the inner islands the tow is lengthened to 200m, which includes a section of 14m of 38mm stud link in the centre, at which stage the barge tends to settle on one quarter depending on the prevailing weather. Clearly, the flat bottom nature of the barge slides well, even when loaded with 1000 tonnes of wet gooey spoil. Once empty the 80 tonne lightweight barge becomes lively again, but makes for an easy lightweight tow as long as there is a substantial vessel in charge upfront. The trap for young players would be to attempt such a long tow into open water and varying sea conditions with a lightweight tug, even if it had coastal survey limits. I can well recall my earlier experience when as a young tow boat master I bit off a bit more than I could chew on Auckland's harbour in a very stiff northerly with a loaded barge in tow and could not stop my track astern. Embarrassing yes, fortunately help was at hand in the form of a port tug who hauled us clear of danger just as the squall abated. Was my foo-foo valve puckering? Of course it was, but a lesson was learnt with no damage. During the 120nm round trip the tug master not only has to contend with tides, wind and the notorious Colville passage, he must also control a heavy barge one way and a lightweight on the way home. This is the first of the new generation alloy dump barges we have been fortunate to review and it is hugely engineered, the internal framing and structure is immense. At this stage images of such remain commercially sensitive, and rightly so. For a dumb clamshell split hopper barge she has appealing lines and a functionality about her that sets her up for the job at hand. As a light ship this barge punches well above her weight, she can carry some 1000 tonnes before creeping towards the load line. This is no mean feat given her size. Her light un-laden weight offers both pluses and negatives, but as in all vessels where a compromise develops, as long as the pluses outweigh the negatives, one has got to be on the right side of the ledger. S P E C I F I C AT I O N S Vessel Name Owner Home port Builder Designer Launched Construction Length (LOA) Beam Depth Draft Hopper Capacity Total load capability T.R. Healy Pacific Plant Limited Auckland, New Zealand Q-West Boat Builders Limited Teknicraft Design Limited January 2013 Marine Grade Aluminium 40.2m 12.5m 3.85m 2.05m 620m3 800 tonnes "The world's leading inspection, vertification, testing and certification company" Marine Surveying, Design Approval and new Construction Survey, Cargo Surveying, Safe Ship Management, Equipment Inspection and Testing (including Radiography, Thickness and Crack Testing etc), Cranes, Lifting Equipment, Pipeline, Boilers and Pressure Vessels Design Verification and Certification, Water and General Laboratory Testing, Vibration and Oil Analyses. ISO 9001:2008, ISO 17925, ISO 17020:2000 NATIONAL SHIPPING OFFICE: 17 Maurice Road, Penrose 1061 PO Box 13 518 Onehunga 1643, Auckland Ph: 0800 174 025, Fax: 09 636 6054 Email: nz.auckland.industrial@sgs.com www.nz.sgs.com VIP.S85 S G S N E W Z E A L A N D LT D OFFICES IN: Auckland, Tauranga, Napier, Rotorua, New Plymouth, Wellington, Christchurch, Timaru, Invercargill, Dunedin May/June 2013 Professional Skipper 15

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