VectRA 3000 an Innovative new VSP Tug brings numerous practical advantages

Sanmar Shipyard is starting the construction of this new VectRA 3000 series of tugs which will be offered as one of the standard deliveries from the yards.

Having been the builders of the world’s very first LNG fuelled tugs, innovative Turkish Shipyard, Sanmar, continues to break new ground by commissioning a completely new design of Voith Water Tractor from equally cutting edge designers, Robert Allan Ltd. Faith in the project is so high that work has already started on the first example at Sanmar’s Tuzla shipyard.

The new VectRA 3000 design, developed exclusively for Sanmar, contains many innovative ideas from both the builder and designer aimed at developing a cost-effective VSP tug for the world market. Sanmar’s brief to Robert Allan Ltd was to create a VSP tug which was under 500 GRT and which would incorporate high-speed engines, electronic controls and be fully MLC 2006 compliant for all crew accommodation. The challenges therefore focussed on the machinery design and the overall layout. As experienced designers of VSP tugs, Robert Allan Ltd had numerous designs from their AVT series available to use as baseline references, but as always each new design is tailored to the specific application and the hull form was developed to reflect the latest lessons learned from extensive CFD modelling of hull performance.

Sanmar shipyard is offering this new VectRA 3000 series of tugs as one of its standard deliveries. Each tug will measure 30.25m in length with a moulded beam of 13.00m and an overall draft of 6.00m.

The most unique aspect of the design is the propulsion arrangement. Driving the forward located Voith type 32-R5 250 cycloid propellers are a pair of Caterpillar 3516C high speed diesels, each developing 2525kW at 1800 rev.min. Instead of the traditional Voith Turbo coupling, the engines are connected to the Voith propulsion through a pair of Reintjes model WAF 843 clutch and reduction gearboxes. This reduces transmission losses, thus increasing the overall propulsion efficiency, and also enables the drives to be de-clutched at idle, significantly reducing fuel burn.

Using high-speed engines also significantly reduces the space occupied by drive machinery and of course results in much lower weight, allowing a finer more efficient hull form for the same deadweight. The installed cost is also significantly reduced. This machinery combination will deliver a bollard pull of up to 70 tonnes and will drive the hull at a predicted speed of not less than 12.5 knots.

This tug also incorporates the new electronic Voith Remote Control™ system. This control is set up to work in a combinator mode whereby both rev/min and pitch increase together at a pre-defined ‘ramp up’. It is believed that this is the first installation of high speed engines with VSP drives in conjunction with the Voith Electronic Control System.

The flush deck layout is relatively conventional for a Voith Tractor, but in compliance with Maritime Labour Convention 2006, all accommodation is on the main deck, with two single cabins for officers and two double cabins for crew, each with private en-suite facilities. The galley and mess area adjacent to a central entry and wet lobby area complete the outfit.

The vessel will be equipped with a DMT Type DMT TWE250kN frequency-controlled electrical drive double drum towing winch with tension indication. Wire capacity is 700m of 54mm steel wire for towing and 240m of 58mm synthetic rope for harbour assistance on both drums. The electric power will be delivered by two 86ekW Caterpillar C 4.4 generator sets.

The VectRA 3000 design will be classed by the American Bureau of Shipping, with the notation *A1, *AMS, Towage Vessel, ABCU, Unrestricted Service, Fi-Fi1, HAB(W8), UWILD.