A Versatile push tug design for German owners

The design is designated the NavTug 18TS ‘push’ and combines the features of a small shallow draft twin screw tug with those of a push boat for use on inland waterways. Measuring 18.50m in length overall, with a beam of 6.20m, the tug has a working draft of between 1.80m and 2.20m and a minimum air draft of approximately 4.3m.

The vessels are optimised to meet the stringent operational and environmental requirements for use in the Port of Hamburg, the Kiel Canal, coastal waters, the upper and lower stretches of the river Elbe and inland waterways. To that end the design and its power plant comply with the latest environmental requirements as per CCNR II and Marpol Annex 6. The tug has an operating permit SUK (Ship Licensing Commission) zone I-IV and is licensed by the SeeBG (Seaman’s Accident Prevention and Insurance Association) and carries the Germanischer Lloyd class notations GL+100 A5K (20) E Tug+ MC AUT and is licensed for 24 hour operation.

A ‘compact’ hull design incorporates a semi-raised foredeck, two push knees in the bow and an open stern. Deck equipment includes two hydraulically powered tension winches for use when pushing, a pair of hydraulic anchor windlasses, each with a capstan head, and a quick release tow hook. An elevating wheelhouse can be raised during pushing operations to give an ‘eye-line’ height of 8m above the waterline. When configured for minimum air draft, the mast and radar mounting can be folded down. Accommodation is provided for a maximum of four persons in three cabins, a mess room and galley.

Two Volvo Penta D16-600 diesels generate a total of 882kW (1,200bhp) to power the twin screw propulsion system. Power is transmitted via ZF W2300 reverse reduction gearboxes to a pair of 1.3m diameter four blade propellers turning in fixed Kort nozzles. This arrangement produces a bollard pull of 15 tons and gives the vessel a free running speed of about 10 knots.

Auxiliary power is supplied by two diesel driven generator sets, one of 27kVa and one of 20kVa. Both are installed within ‘Silent Pack’ acoustic housings. Christian was formally named in April and has now joined the Schramm fleet of five existing vessels based at Brunsbuttle, at the junction of the Elbe and Kiel Canal. The first tug of the series, the Moin, was completed in January for H.S.H (Hafen Service Hamburg) and is carrying out a wide range of duties, including barge work, support for marine civil engineering, port services and pollution control. Both tugs were completed by the shipyard of Gebr Friedrich GmbH & Co KG of Kiel using hulls and major steelwork constructed in Poland.