Flexible trading emphasised on Suezmax design

Diamond S Shipping’s trading philosophy is to have a young fleet of high-quality ships, time charters with profit shares, and a spot fleet that can take advantage of cyclical upswings. The latest addition to the spot fleet is the 158,000 dwt crude and clean product carrier Sabine.

Built to ABS class at Samsung’s Geoje shipyard, the vessel’s basic design was modified to at least meet, if not exceed, industry standards and oil major requirements. To maximise the vessel’s trading flexibility, particular attention has been paid to mooring and ship-to-ship transfer capability.

The vessel has six mooring winches and two windlass/mooring winches. This allows for 16 mooring lines available at drum, which means the vessel can moor at any terminal in the world. As well as meeting OCIMF mooring equipment guidelines (1997) all the SPM equipment and mooring fittings include underneath stiffening to provide greater stability.

The mooring winch brake drums are of SUS type and so are virtually maintenance free. Non-asbestos brake lining has been applied. The hydraulic power pack units for the mooring equipment compartments are all fitted with an oil mist detection system to detect potential oil leaks on the hydraulic equipment. This anticipates forthcoming industry requirements.

Mooring fittings with a high bollard pull have been installed on the starboard side. These allow Sabine to carry out ship-to-ship operations with tankers of all sizes. The vessel has vapour return manifolds and all vapour emission control measures are as per United States Coast Guard requirements. These features mean Sabine is able to carry out lightering operations at any location. An SBM chain block and pick-up arrangement has been installed in line with OCIMF requirements. This allows the vessel to carry out cargo operation at SBM.

To support easy transfer of personnel when Sabine is operating in offshore/remote locations, the deck has clear markings for helicopter landing.

Staying on deck, the accommodation ladders are well clear of the hose-handling working zone and sunken bits have been provided on the shipside for securing pilot ladders and accommodation ladders, in compliance with Australian marine pilot regulations. Air-operated travelling type pilot ladder hoists have been installed on both sides.

On a conventional vessel of this size there will typically be one hose-handling crane with a safe working load of 15 tonnes. At the owner’s request, two hose-handling cranes have been installed with safe working loads of 20 tonnes and with a maximum outreach of 7.5m to shipside in order to meet the requirements of certain oil majors and terminals. This capability also allows the vessel to handle the heaviest SBS hoses presently in use in the industry.

The cargo manifolds are 17.6m x 8.3m above the waterline in normal and summer conditions. Sabine has the necessary reducers and arrangements to drain lines and transfer spillage if necessary.

A flexible and easy to operate cargo system is another hallmark. For easy cleaning and quick changes between cargoes there are no internal structures between the cargo tanks.

Sabine has six pairs of cargo tanks and two fully coated slop tanks. At the construction stage it was decided to apply Sigma Phenguard phenolic epoxy in the cargo tanks, even though this was not in the original specification. It was felt the additional investment would justify itself through an extended coating life given the range of petroleum products (including reformatted gasoline, which has a high alcohol content) that could be carried in the tanks.

Hyundai Heavy Industries steam turbines power the vertical centrifugal cargo-pump capacity of 3,800 m³/h each. A reciprocating double-acting stripping pump of capacity 240m³/h and stripping eductor of 600 m³/h are also incorporated in the system.

The vessel has a maximum loading rate of 12,000 m³/h, and a maximum loading rate through each segregation of 4,000 m³/h and in each tank 2,000 m³/h. The maximum discharge capacity is 11,400 m³/h – 3,800 m³/h per segregation and 1,900 m³/h from each tank.

Steam-heated coils made of aluminised steel are used to heat the cargo. Cargo in the tanks can be heated to 60^oC.

Two electrically driven ballast pumps with a capacity of 2,000 m³/h perform ballast and deballasting duties across the vessel’s 12 ballast tanks that have a combined cargo-carrying capacity of 51,819m³. A ballast eductor of 300 m³/h capacity is also part of the ballast system.

To support fuel saving the hullform has been optimised. The hull is protected by a KC impressed current cathodic protection system, and coatings have been supplied by Jotun. The ship has been designed to support underwater survey in lieu of drydocking. The sea chests are fitted with aluminium anodes guaranteed for five years.

To inert the spaces, Kashiwa plant (capacity: 14,250 m³/h) has been installed. Each cargo and slop tank also has a PresVac high-velocity venting system and a connection on each independent vent line to the common vapour return line. Flue gas is drawn from two vertical Aalborg auxiliary boilers.

For tank cleaning, Sabine is equipped with 28 fixed Polar Marine machines with a capacity of 75 m^3/h. To calculate the number of fixed tank cleaning machines needed, shadow diagrams were prepared for all of the cargo and slop tanks. Also on board is a tank cleaning heater of 240 m³/h capacity capable of heating seawater from 20^oC to 79oC.

The cargo control room is situated on the A-deck in the accommodation. It houses the cargo control console, Samsung cargo monitoring system, Sel Seres ODME, online cargo loading computer, and Riken Keiki fixed gas detection system control cabinet for ballast tanks.

The accommodation entrance upper deck is home to the air condition system, Emerson Rosemount Radar Cargo tank level gauging system and wind speed/direction repeater. Ship’s office/conference room is situated adjacent to the cargo control room: they share a common door.

Sabine has a conventional wheelhouse. Principal navigation equipment includes two JRC X band/S Band Radars and ARPA, Tokyo Keiki Gyro Compass/Auto Pilot, Samsung JRC Radio Plant and two JRC ecdis along with a full set of paper navigation charts. Satellite communication is via JRC FB 500 and a Globe Wireless i250 system. The Globe i250 allows the user to make voice calls using a GSM handset or normal fixed-line telephone, send/receive e-mail and fax, browse the Internet, and up/down load files. It also allows users to access Globe Wireless commercial applications. The solution includes a dual firewall, highly optimised IP connections, and multiple least-cost route gateways.

There is a bridge manoeuvring system console on the starboard bridge wing for ship-to-ship operations. The wheelhouse front glass windows have been provided with a hot air defogging system. Shutter-proof film has been installed on the front windows of the bridge to support navigation when transiting high-risk areas.

The radar mast is of a non-collapsible type and the maximum air draft of the vessel has been reduced to 49.79m with a view to US trading requirements.

All crew and living quarters are covered by smoke/flame gas detectors. The pump room has an independent gas detection system.

A Kashiwa high-expansion foam system protects the engineroom, and the cargo area is protected by an NK Fire foam system.

In the engineroom, a MAN B&W 6S50MCC7 develops a total of 18,215kW for a service speed of 15.9 knots. A medium gas oil chiller unit allows the engine to switch between low sulphur distillate fuel and 600 centistoke heavy fuel. Starting and service air are provided by Tamrotor compressors.

Electric power plant is powered by three Yanmar Diesel generator engines of 840kW each, which can be operated both on 600 centistoke heavy fuel at 50^oC and low sulphur distillate fuel.

Two Aalborg 35,000 kg/h auxiliary boilers supply steam for cargo system operation, cargo heating and the engineroom. To ensure that the incinerator is fully compliant with Marpol regulations, it was upgraded to a 700 Kcal/h model. For the same reason the oily water separator was switched from the conventional filtration model on the original maker’s list for a state-of-the-art Alfa Laval Centrifugal type.

Space has been kept aside for future installation of ballast water treatment plant.

Samsung saver fins have been installed to enhance the vessel’s powering performance. These are well known on the market. They comprise four steel blades: two on the port side and two on the starboard side. They guide the flow of sea water to the propeller and tests have shown that they help reduce fuel consumption by 2-3 per cent.

A Mitsui propeller boss cap fin has been installed on the propeller to reduce fuel consumption. The vessel also has a Kyma performance monitoring system. The yard calculated the vessel’s Energy Efficiency Design Index and found that Sabine registers 3.317 g-CO₂ per ton-mile versus MEPC 62’s reference value of 3.534 g-CO₂ per ton-mile.

The steering gear on Sabine is a conventional four ram type supplied by Hatlapa (Korea). The rudder is of semi-balanced streamline type. The rudder trunk is provided with an anti-stowaway protection grid. Circulars from various insurers and class societies have made clear that stowaways hiding in ships’ rudder stock recesses, especially at African ports, are a persistent and growing problem. Typically stowaways wait in port areas until after dark and then swim to the rudder stock, climb it and hide inside the recess, making it difficult for the ship’s crew to find them.

For satellite communications, Diamond S has invested in Fleetbroadband 500 and Fleetbroadband 250, which the company says provides sufficient bandwidth. All navigational updates like ENC, ADP and NTM are received electronically via satellite data transfer.

For crew welfare, recreational facilities include a fully equipped gymnasium, table tennis, board games, large LCD TV, and a sound system for lounges and senior officers. An excellent innovation is the iFusion communication system, which allows crew to have their own GSM mobile, SIM card for voice and SMS communication, through pre-paid billing without affecting the ship’s official communication system.

The delivery of Sabine brings the Diamond S Shipping fleet on the water to 38 tankers with an average age of two years. Two further vessels were on order for delivery following Sabine: the 158,700 dwt Suezmax Colorado at Samsung and the 158,300 dwt Frio at Hyundai Heavy Industries. TST