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in the Amazon, as well as some of the big river systems in

Africa that are growing along with the oil business,” said van der Vegt. For example, the rudder propeller solution, particularly the deck-mounted version, is particularly at- tractive in remote areas where there are a dearth of marine facilities or infrastructure, as the deck-mounted unites are easy to maintain and replace without the need of a ship- yard. In addition, many emerging markets want to build the boats locally to feed the local market, and with the deck-mounted solution, the countries can build their barg- es locally than easily add the propulsion solution. “The advantage in push boat performance is you have cleaner thrust coming through the kort nozzles, so there is not a parasitic loss of the propulsion power that you have in a traditional vessel,” said van der Vegt. “So you get more pure directional thrust pushing, pulling and turning the tow. You can get equivalent performance in a smaller power output, and so we are seeing with the tug fl eets they are able to use smaller engines, meaning they are lighter, and with less weight penalty they are more fuel effi cient.” “A 1400 hp pushboat (with the Z-Drive) can perform the same as a conventionally outfi tted boat with 2000 hp– same barges, same loads – as each thruster has full power at 360 degrees. With traditional systems you only have full power in one direction.”

While azimuth thruster technology comes with a num- ber of advantages, the main reservation has been that the

Z-Drive – which hangs below the vessel – is more vulnera- ble to damage than traditional systems, particularly on the shallow draft, oft changing and sometimes litter-strewn inland waterways.

Here the ZF global network of supply comes into play, as it realizes that keeping a boat in revenue service is JOB 1 for these operators. To that end, it emphasizes that a key strategic advantage is that – if the unit is installed as a top-mount thruster – it can be pulled and replaced with a swing unit easily and quickly – sometimes between eight to 10 hours – while the boat stays in the water.

Engineered Solutions: Just in Time

A key challenge in any manufacturing business is con- trolling costs in the design and production shops, and the

ZF Marine thruster business is no exception. In fact, as this business unit produces no ‘standard’ units, it is particularly adept at looking at the project as a whole to design with the naval architect, with the shipyard and ultimately with the owner what is agreed to be an optimal solution. “If a client comes in and says ‘I want a 2000 horsepower boat,’ our fi rst questions are: What do you want to do with the boat?; What are you going to be pushing?; What kind of thrust do you need?,” said van der Vegt. He explained that thrusters can offers several power and maneuverability ad- vantages; for example of a vessel outfi tted a traditional power train may require a 2000 hp power plant, whereas a vessel out- fi tted with a thruster may need only a 1400 hp power plant, offering substantial space, weight and fuel consumption ad- vantages . “We want to offer an optimum solution based on what the client wants to do with the boat, and the interaction with the client is crucial” because it doesn’t manufacture and house standard thrusters that are simply off-the-shelf.

Nevertheless and despite the custom nature of each or- der, ZF delivery times range between fi ve and eight months, which is a key plank in extending its platform in North

America as he said U.S. shipyards build boats faster than its

European counterparts. And today, they are building a lot of them. ZF aims to be there, when they do. So far, so good.

INNOVATIVE PRODUCTS

Frank van der Vegt,

Sales Manager, Commercial

Craft Thruster Systems, at the ZF

Marine Krimpen B.V. 42 MN

October 2014

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