Push Boats: From Turkey to Brazil

The shallow draft market in South America continues to strengthen, powered by orders such as Hidrovias do Brasil S.A. 2013 deal for eight HB Pushboat ASUNCION-PYs, which represents a new generation of powerful Shallow Draft River Push Boat designed specifically for South America inland waterways logistics. Robert Allan Ltd. (RAL) designed and Vienna Model Basin optimized, the total deal for eight push boats is customized for Hidrovias do Brasil S.A., a river iron ore transport subcontractor company for Vale. The boats are designed to meld power with maneuverability in a 69 ton bollard package.
The main concern of the ship operator were shorter river voyage times with sophisticated power management technology, shallow draft with increased deadweight of speed, improved sea keeping ability, increased crew comfort, higher escort force performance, high propulsion technology, greater endurance, low emissions and low fuel consumption. The vessels will be used for inland waterways logistics from Colombia in Brazil to Argentina and/or Uruguay through the Paraguay-Parana waterway.  The total distance is over 2500 km, much of it navigating through extremely curvy river sections which make excellent maneuverability a necessity.
An additional crash stop requirement of 2.5 flotilla length proved to be a guiding factor. The flotillas will consist of one push-boat pushing 16 barges, with a total capacity of 40,000 dwt. The boats will be pushed hard, operating 24 hours per day, 11 months per year.
UZMAR worked with Robert Allan Ltd., which conducted extensive CFD analysis to meet demands for maneuverability maximized fuel economy and to comply with the crash stop requirement. As a result, the hull shape, tunnel geometry and propulsive components have been optimized for those specific requirements. This was then verified by a series of model tests conducted at the Vienna Model Basin in Austria.
The result of the deep researches created the new generation pushboat which is a 45.6 m length overall, a 16.5 m beam, a 2.1 m draft at the dry season and a 2.4 m draft at the wet season, with a 7200 bHP diesel-electric HFO powered push-boat with azimuth drives and propellers in nozzles configured for shallow water operation.  The DE system is an AC variable rpm controlled designed and integrated by approved ABB system integrator Elkon/Imtech with complete ABB components. During the sea trials, maximum bollard pull (69 tons) and speed of 13.2 knots were displayed performed.  
UZMAR SDP 4600 Pushbaot is a strong contribution to Hidrovias doBrasil’s dedicated strategy of developing a modern and internationally competitive inland waterways logistics.
The diesel electric system is designed and manufactured by Turkey’s leading ship electrical engineering and manufacturing company ELKON with ABB power electronics and supervision, which is a member of IMTECH Group. These push boats are propelled by a state-of-the-art diesel-electric propulsion system, with three main diesel generator sets providing 3 x 1,710 ekW of power to 3 x 1,600 kW motors, each driving a Schottel SRP 1215 Z-drive with nozzle modified for shallow draft operation. The major electric components (AFE drives, propulsion motors, generators, etc.) are ABB components, supplied by Elkon. The generator engines are three Wärtsilä 9L20, medium speed diesels, each producing 1,800 bkW at 1,000 rpm. When a low level sailing speed/power is required on board, the first engine starts at full load where the Verified Frequency Drivers separates the power to the propellers evenly. If the power requirement reaches up to 40%, the second engine starts to feed the propellers, and the third engine follows this routine when the power requirement reaches to 70%. This modification is designed to provide high fuel efficiency and longer life circle for the main engines and low CO2, NOx, SOx and PM emissions. These push boats will run on HFO, with the ability to operate on MDO, if needed. Each push boat has a total fuel capacity of 500 cu. m. of HFO and 30 cu. m. of MDO, and a ballast capacity of 400 cu. m.  The potable water capacity of 34 cu. m. is supplemented by two onboard flash evaporator units.

Builder:
UZMAR Workboat and Tug Factory
Designer:    Robert Allan Ltd.
Operator:     Hidrovias do Brazil
Country:     Brazil
Flag:     Paraguay
Total number of sister
ships completed already:     6
Contract date:     2013
Delivery Date:     Q1 2015
Length, oa:     45.6m
Breadth, moulded:     16.5m
Design, draft:     2.1m
Service Speed:     13.2 knots
Bollard Pull:     69 tons
Classification:     BV
Navigation area:     Inland Waters
Main engine(s):     Wärtsilä 9L20
Make:     Wärtsilä
Number:     3
Fuel:     HFO, with the ability
    to operate on MDO
Output of each engine:     1,800 bkW
    at 1,000 rpm
Propeller:     Schottel SRP
    1215 Z-drive
Number:     3
Propulsion:     Diesel-electric
    propulsion system
Propulsion Power:     3 x 1,710 ekW
Complement:     18
Crash Stop Requirement with adopting the Frequency Mode Effect Analyses

 (As published in the March 2015 edition of Maritime Reporter & Engineering News - http://magazines.marinelink.com/Magazines/MaritimeReporter)