Customised Shoalbuster for Smit Lamnalco

Designated a Damen Shoalbuster 2508 SD, this shallow draft Shoalbuster variant will be deployed to Smit Lamnalco, Gabon, and registered under the Panama flag. This particular Shoalbuster is capable of towing, mooring, pushing, and dredging support duties in the usual way but is extensively customised to suit the client’s particular requirements.

SL Mbissi measures 24.82m in length, with a beam (moulded) of 8.00m, a depth (at sides) of 2.99m and a draft of only 1.8m (approximately) with specified tank capacities. Dedicated tanks are provided for 43.0m3 of fuel oil, 11.00m3 of fresh water, 3.8m3 of sewage, 2.1m3 of dirty oil, 1.4m3 of bilge water and 0.25m3 of dispersant contained in a loose deck tank.

The vessel is 170 gross tonnes and classed by Bureau Veritas: 1+HULL *MACH Tug Unrestricted navigation, AUT UMS, IWS.

The hull is flush decked, with some sheer towards the bow, with the usual double chine construction and shallow tunnels to accept the nozzles and propellers. Unlike the usual Shoalbuster configuration, the deep central push knee has been replaced by a bow fender of moulded rubber blocks. Set back from the stem is a short central skeg housing the bow thruster in normal Shoalbuster style.

Two Caterpillar C18 ACERT main engines develop a total of 1,000bkW (1,360 bhp) at 2,100 rpm to drive a pair 1,400mm diameter Promarin fixed pitch propellers via Reintjes WAF 264 gearboxes. The propellers rotate in DMC Optima nozzles.

On trials SL Mbissi achieved a speed of 11 knots and an average bollard pull of 19.3 tonnes and 19.7 tonnes maximum, at a draft of 1.75m.

A major customer requirement was that the deck machinery and bowthruster should all be electrically powered. Unlike virtually all previous Shoalbusters, SL Mbissi has three identical Caterpillar C4.4 auxiliary generators rated at 86.25kVA 230/400V AC located in the engineroom. Control and load sharing are automatic. In practice, one generator is online when the tug is underway, two when the bowthruster is also required and three when the bowthuster and winch are both in use. A bonus for the operator is additional redundancy with three relatively small generators, no requirement for a diesel powered hydraulic pump, and ease of maintenance.

The vessel’s after deck is a large clear space, with timber protection, and no stern roller or crane. A single drum Kraaijeveld electrically powered towing winch is fitted and equipped with a 200m towline of 40mm diameter steel wire rope. The winch has a brake load of 50 tonnes and a line pull of 30 tonnes at 6.5m/min or 9.5 tonnes at 24m/min.

A Megator Mega Spray system is fitted for use with chemical oil dispersant during pollution control duties.

SL Mbissi is equipped with an extensive outfit of navigational and communications equipment to GMDSS Area A3 standard. Fully airconditioned and heated accommodation is provided for up to six persons in two single and two double berth cabins.