The South African National Ports Authority has taken delivery of Shasa, the first of seven powerful Voith powered tractor tugs.
The South African National Ports Authority (Transnet) has taken delivery of Shasa, the first of seven powerful Voith powered tractor tugs. Ordered from South African Shipyards of Durban, Shasa and the next pair of tugs in the series are to be based at Port Elizabeth to serve the new deepwater container port of Ngqura, 20km away.
The tug "Shasa". Transnet is building seven tugs of this new class for South African ports. Durban naval architect Peter Volschenk was responsible for the design of this new generation of South African shiphandling tugs, working in close cooperation with the Marine Division of Transnet. In keeping with past practice, Transnet chose to stay loyal to the Voith Schneider propulsion system, used successfully in their harbour tugs in other South African ports.
Shasa is a vessel of 31m in length overall, with a breadth of 11.5m and deep draft of 6.18m. A traditional round bilge tractor hull form has been adopted, with a large skeg and heavy fendering at the stern.
A pair of Voith 32R5/265-2 cycloidal propeller units is installed, each with five blades and a blade orbit of 3.2m in diameter. The units are powered by a pair of MAN 8L27/38 diesel main engines rated at 2,640kW each at 800 rpm (total approximately 7,174 brake horsepower).
A bollard pull of 70 tons was specified for the first three tugs and 60 tons for the remaining quartet. On trials Shasa exceeded the predicted bollard pull with an exceptional figure of just over 80 tons.
Deck machinery includes a hydraulically powered Rolls-Royce ? Brattvaag towing winch, a Palfinger PK12080 deck crane, and a 3.8m Gemini rescue boat and davit. A single 480kg stockless anchor is handled by a windlass from Petrel Engineering.
Shasa is equipped for fire fighting to FiFi 1 standard, with two Counterfire water-foam monitors mounted aft of the wheelhouse. A pair of 1,200 cu/m/hr fire pumps are driven via Kumera "step-up" gearboxes from the main engines.
Electrical power is generated by two Cummins 6B/BT5.9-D(M) 91 kW alternators, supplying the vessel"s systems via switchboards from Siemens.