• 2015 August 2 11:51

    Robert Allan Ltd. offers optimized tug-barge system designs for South America

    Some veteran Mississippi push boats and barges have been transported to South America for second careers. However, conditions on a great river like the Paraguay-Paraná are different. It has sharp bends, shallow stretches, and includes remote reaches totally lacking in infrastructure. Building on extensive experience designing for the shallow rivers of Canada's frontier northland, Robert Allan Ltd., Naval Architects from Vancouver, BC have taken on the challenge of creating a new generation of specialized tug and barge systems to suit these demanding environments, the firm said in a press release.

    A waterway logistics corporation, Hidrovias do Brasil, was the firm's first South American client to commission new purpose-built shallow draft vessels. These would serve a major mining company's plans to transport iron ore from Brazil down the Paraguay-Paraná to Uruguay in a 24 hour-a-day, year round operation. The sprawling watercourse flows south through the centre of the continent, connecting Brazil, Bolivia, Paraguay and Argentina. The transit voyage for the convoy covers 2,500 kilometres from Corumba to Nueva Palmira.

    According to Robert Allan Ltd. President Michael Fitzpatrick, "The shallower it gets, the more challenging." Accurate design is even more critical than normal, and the firm was challenged to develop vessels capable of operating throughout the variable river system, especially in seasons of low water levels. Project Engineer Erik Johnston adds, "fuel consumption was calculated with simulations to match the load profile, using data from the river; less water under the keel means more fuel consumption."

    After closely studying the region and client requirements, the firm developed a powerful 46.5 metre by 16.5 metre push boat design with a full load draft of 2.5 metres or at a reduced draft of 2.1 metres for low water conditions. A double hull mitigates the risk of a fuel spill resulting from any grounding or collision damage. Each pusher tug can handle 16 barges in a 4 by 4 array, creating a convoy spanning 290 metres by 60 metres and carrying 45,500 tonnes of ore at the current river draft limit. The barges can carry up to 50,000 tonnes per convoy at a 3.96 metres draft. A critical requirement for the project approval was the Brazilian Authority's performance stipulation for a crash stop: fully loaded, running downriver from full speed in 2.5 convoy lengths. The Authority made the crash stop an important safety measure on this river with varying channel width and depth, limited sightlines around bends and increasing vessel traffic. The Robert Allan Ltd. team examined many propulsion alternatives, and finally developed the triple azimuthing drive tug design to satisfy this demanding requirement. This drive arrangement allows immediate full reverse thrust and outstanding manoeuvrability. This backing performance was verified in advance through an extensive series of computational fluid dynamics (CFD) analyses.

    Eight of these push boats, designated as the RApide 4600–Z3 Class, were constructed by Uzmar Shipyard in Turkey. Each tug has accommodation for eighteen crew and a range of over 5,000 km (one full round trip) at the deep draft of 2.5 metres, or a one-way trip at the 2.1 m draft. The bridge offers an unobstructed view of the tow ahead and all working decks, and there is plenty of deck space for handling lines.

    These are the most powerful triple Z-drive shallow draft push boats built to date. The propulsion system is diesel-electric, with three independent Wärtsilä 9L20 medium-speed diesel gensets each developing 1,710 ekW. AC current motors from ABB power Schottel SRP 1215 azimuthing drives with custom-designed nozzles that reduce draft and heavy-duty drive components to withstand impacts with river debris. This combination produces a Bollard Pull of 69 tonnes ahead and 63 tonnes astern. The engines are capable of operating on MGO, but normally run on less expensive HFO. Diesel-electric propulsion provided advantages with flexibility in positioning the engines and drives to ensure best operating trim in the shallow waters.

    There are 128 open hopper barges, each measuring 61.0 metres by 15.0 metres also designed by Robert Allan Ltd., were constructed at Shanghai Zhenhua Heavy Industry Co. Ltd. (ZPMC) in China. Half the barges have single raked ends, while the remainder have no rakes. The barge rakes were also optimized to improve the crash stop capability as discussed above. Bart Stockdill is the project engineer leading the CFD team. He notes, "We were able to compare our own hopper barge design with the ones designed by a local shipyard for this project. Ours had 7% less resistance representing a very significant fuel savings." Robert Allan Ltd. also designed an 1,800 tonne floating drydock to service the new fleet, which was also built by ZPMC, and is now in operation at Asuncion, Paraguay. The barges were delivered 32 at a time by heavy lift ship (Figure 2) to Montevideo, Uruguay. Sixteen additional hopper barges are being constructed at CIE shipyard in Paraguay.

    Robert Allan Ltd. is an independent, privately owned firm of Consulting Naval Architects, established in Vancouver. The business was founded in 1930 when Robert Allan commenced private practice as a Consulting Naval Architect after managing a local shipyard. He was responsible for numerous enduring designs produced for the growing British Columbia fishing fleet and for coastal ferry services, among others. The firm's reputation was also enhanced by the design of the notable and enduring ocean-going motor yachts Meander and Fifer.


2024 March 28

18:05 Jan De Nul, ENGIE and Equans launch a pilot project centred around the use of Vanadium Redox Flow batteries
17:35 Latvian port equipment manufacturer Bleste introduces new bulk handling ‘bucket’
17:05 Investors upgrade Navios Maritime Partners
16:25 DEME reports 22% increase in the orderbook and a record-high turnover of 3.3 billion euros in 2023
16:14 MABUX: Bunker Outlook, Week 13, 2024
15:41 AD Ports Group announced the opening of Saadiyat Marina & Ferry Terminal and Rabdan Marina
15:11 Sydney invests $11.5 million in two new operational vessels designed by Incat Crowther
14:55 China’s Jinzhao wins Peru $405m port construction contract
14:13 APM Terminals Moín handled six million TEU
13:48 ClassNK grants Innovation Endorsements for Products & Solutions to two innovative initiatives by MOL
13:37 Konecranes launches its flagship Konecranes X-series industrial crane
12:53 United European Car Carriers UECC spearheads collaboration with industry leaders to advance CNSL as a sustainable marine fuel
12:26 Ocean Network Express announces Transpacific service
11:48 Yang Ming announces 2025 Trans-Pacific service network
11:24 Fincantieri signs contract for the supply of two PPAs to Indonesia
10:42 Maersk transported more than 660,000 TEU using clean fuel in 2023
10:23 Documentation delays push industry costs to $3bn
09:48 PONANT and FARWIND Energy partner to develop green hydrogen refueling solutions

2024 March 27

18:22 Bureau Veritas awards world’s first prototype certification for SolarDuck’s floating offshore solar solution
17:58 The recently converted Allseas's shallow water pipelay barge starts preparations for its first commercial project
17:38 The Port of Rotterdam calls on the European Commission and Parliament to focus on actively promoting green energy
15:23 SEFE to become sole shareholder of WIGA
14:53 Ocean Installer secures yet another SLM contract with Equinor
14:23 Cadeler signs offshore wind turbine installation contract for the vessel Wind Scylla
13:42 Carnival Cruise Line orders 5th Excel-class cruise ship
13:11 Maersk and MSC overcharging cargo owners for EU ETS, says T&E
12:52 The Port Authority of Valencia launches the ZAL project in the Port of Valencia
12:11 Clarkson Port Services and Peak Group collaborate to deliver Port Agency services across the North Sea
11:42 Wan Hai Lines holds ship naming ceremony for new vessels
11:24 Consolidated shipping lines EBIT loss was $1.44 billion in Q4 2023: Sea-Intelligence
10:49 Seaspan Shipyards receives long-term contracts for the pre-construction work of the the Canadian Coast Guard's first six multi-mission vessels
10:14 Woodside completes sale of 10% scarborough interest

2024 March 26

18:02 COSCO Shipping Lines introduces new Americas service
17:30 Davie awarded first contract for design of icebreaker fleet under Canada’s National Shipbuilding Strategy
17:04 Sanctions complicate Arctic LNG ship sales, Hanwha Ocean says - Bloomberg
16:57 Terntank places an order for 1+1 additional wind/ methanol-ready hybrid tanker
16:28 BW LNG completes acquisition of two TFDE vessels from Stena Bulk
15:50 Hanwha Ocean develops VR-based special vehicle simulator
15:20 TotalEnergies and SINOPEC join forces to produce sustainable jet fuel at a SINOPEC's refinery
14:52 Wärtsilä Lifecycle Agreement to guarantee operational reliability of new wind farm installation vessel
14:23 Hudong-Zhonghua launches two LNG carriers
13:51 Cargo ship hits Baltimore’s Key Bridge
13:12 Final sanctioned tanker with Russian Sokol oil to reach China port - Reuters
12:42 Adani Ports acquires 95% of Odisha's Gopalpur Port from SP Group for $162 million
12:21 IHI and Yara Clean Ammonia agree to jointly assess clean ammonia business collaboration
11:41 Yara Clean Ammonia and Azane granted safety permit to build world's first low emission ammonia bunkering terminal
11:16 Wartsila and Royal Caribbean Group celebrate 15 years of collaboration on digital transformation
10:46 A global carbon tax on shipping is coming, says ABS Chairman and CEO
10:21 Eni, Fincantieri and RINA establish partnership for maritime transport decarbonization

2024 March 25

18:07 The Maritime and Port Authority of Singapore continues to investigate reports of oil spills off the port of Tuas
17:31 “K” Line, NIPPON HAKUYO and OPT Gate sign an agreement for a new fire detection system for car carriers
17:07 Greek merchant fleet recorded slight decline in January 2024
16:47 Hanwha Ocean Plans to develop green technology and naval ships
16:25 U-Ming Singapore and ITOCHU sign milestone MoU for the joint development of ammonia dual-fuel and de-carbonized vessels
15:34 Svitzer targets methanol-fuelled MAN 175DF-M engine for tug application
15:04 Wallenius Wilhelmsen signs contracts for four 9,300 CEU vessels with China Merchants Jinling Shipyard
14:40 Taiwan International Port to upgrade terminal facility at Kaohsiung
13:59 Сruise ship Carnival Freedom catches fire near Bahamas
12:59 Hanwha Ocean wins 2.4 tln-won order for 8 LNG ships
11:16 Inland Ports meet in Paris to talk about the innovation potential of inland ports
10:50 IMO agrees possible outline for maritime “net-zero framework”
10:24 Hapag-Lloyd to continue to avoid the Red Sea route
09:58 QatarEnergy enters time charter agreements with Nakilat for the operation of 25 LNG vessels

2024 March 24

16:18 Inchgreen Marine Park upgraded as part of £11m investment
15:14 A ribbon-cutting ceremony for Solent Rail Terminal Rail was held at the Port of Southampton
14:08 ESNA and Strategic Marine join forces to offer Surface Effect Ship (“SES”) Crew Transfer Vessels (“CTV”) to the market
13:07 First LNG powered vessel calls at HIP
12:49 Inter-array cable installation completed at Neart na Gaoithe offshore wind farm
11:32 Equinor ASA posts net income at USD 11.9 billion in 2023
09:25 Edda Wind announces the sale of Edda Passat