Page 58: of Marine News Magazine (November 2015)

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PROPULSION and service. Chris Senner ing areas. “We found a partner in Steerprop that explained, “We often work While converting an ex- with multiple naval archi- isting standard con? gura- shared a very similar ideology to Reintjes tects to assist in the design tion vessel with z-drives is – both companies solely focus on one of the propulsion package. possible, it isn’t necessar-

For this particular project, a ily practical. The Shearer component of Marine Propulsion, and mutual customer requested Group has completed such that we work with Shearer, conversion designs for cli- both offer products known for their robust using our industry experi- ents, but Sebastian adds, construction, reliability, and longevity – ence and their design ca- “That kind of job repre- pabilities relating to z drive sents technical challenges we knew that Steerprop would be a good applications to create a new and is never an easy task.” towboat, designed speci? - This hull, in contrast, was ? t for inland customers, as well.” cally for the use of z-drive designed from the ground – Karl Senner propulsion for brown water up to match the Steerprop applications” solution, maximize the ef- ? ciencies of a z-drive boat and to reduce vibration.

U D – B - -PNIQUE ESIGN UILT FOR URPOSE

For example, the collaboration between the three groups

The new propulsion package is just that – a package. It incorporates an 8’-6” draft, with attention towards the ? ts well into a built-for-purpose newbuild scenario – es- 9’ controlling depth on inland waterways (but not al- pecially the new inland pushboat design produced in con- junction with partners Steerprop and the Shearer Group. ways achieved by USACE dredging). That lets the boat

On the other hand, retro? tting existing vessels, says Chris do its job in today’s real waterway conditions. Senner

Senner, is considered only on a case-by-case basis. He adds, told MarineNews, “For a vessel designed to operate in the “We have repowered several offshore vessels in the past and ‘ditch’ between New Orleans and Houston, the operator converted them to Steerprop propulsion; similar projects and naval architect both agreed that we should keep draft can be accomplished for inland vessels as well.” That said, to a minimum, and target under 8’-6” to stay off the bot- the towboat designed speci? cally with Steerprop in mind tom.” But, that’s just one of the many advantages that the is the best candidate for this concept and provides the best new towboat offers.

Steerprop’s fabricated steel housing is typically stronger returns in terms of performance, safety and ef? ciencies.

For their part, this design package that involves z-drive and lighter than cast versions. They are also easier to repair if needed, and have shown no signs of corrosion or erosion. propulsion is not the ? rst that the Shearer Group has un- dertaken. Each project, says the Shearer Group’s Joshua These features are a sure bene? t for Inland Operators.

Many factors come into play when selecting the appro-

Sebastian, is different and involves a lot of analysis and many variables to take into consideration. In contrast, he priate thruster for the application: operating pro? le of the says, “Many times, designers never revisit the hull shape to vessel, operating environment, thrust demand, depth re- ensure the best ? ow into the propulsion on a hull designed strictions, bottom composition, risk of impact, and even ‘tier’ emissions requirements can come into play. These for another propulsion system.” The Shearer Group de- signs each hull to a client’s speci? c needs, tailoring the hull factors, say Senner, are all critical when selecting the most appropriate unit for the job. shape for the desired propulsion con? guration and operat-

A Built-for-Purpose Towboat at a Glance …

Length: 90' Design Draft: 8.5' Fuel: 50

Breadth: 39' Berthing: 7 Potable Water: 10

Depth: 10.5' Lube Oil: 1,500 Gallons Slop Oil: 1

November 2015

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