Commissioned by Eureka Shipping of Oslo, Norway, Royal Bodewes has developed and built a 6,145 DWAT cement carrier named Furuvik.
Contracted at the end of 2014, Furuvik was handed over to her new owners in the final week of February 2017. She then left the Eems harbour of Delfzijl, on her way to Denmark for the first commercial voyage.
In the week prior to delivery, an extensive programme of sea trials and performance tests was conducted, during which the proper functioning and safety of all systems were verified and confirmed.
The naming ceremony of yard number 766 was held on February 17, 2017, by Mrs. Hilary McKnight, partner of Mr. Ken McKnight, CEO of the Finnish charter operator of Furuvik.
Built for a lifetime of at least thirty years, Eureka Shipping wants to use Furuvik for the transport of cement and fly ash along the Finnish coast in collaboration with charter operator CRH. For that reason, Royal Bodewes was challenged to design this complex ship with a restricted length, based on the many specific needs of the client, with the proven UAL series as a basis for her development.
Furuvik, named after a Swedish village, is the first in a series of two cement tankers ordered by Eureka Shipping. The ambition of the Norwegian ship-owner is to regenerate and rejuvenate their fleet and to make it more efficient.
The carrier is a self-discharging cement tanker, with all facilities on board for (un-) loading either pneumatically or mechanically, also featuring dedicated unloading equipment for transfer onto trucks. These self-unloading capabilities, combined with her restricted length, makes Furuvik a very practical vessel, which can also be used on many other routes, even where there are no on-shore provisions for loading and unloading.
Fluid Dynamics and Economics
The 4,318 GT cement carrier is based on the Bodewes Eco Traders that were used for the UAL series, as described above. The UAL series were built for Nescos Shipping, also established in Hoogezand and related to the Royal Bodewes Group.
Therefore, Bodewes has a ringside seat to take full advantage of practical feedback from ship’s crews to further improve their design. In response, they developed a hull shape and layout that is able to load and transport cargo in an economically and environmentally sound way.
The hull design of the cement carrier is characterised by a Groot Crossbow. Allowing the ship to cut through the waves, as such reducing the ship’s resistance, this striking feature ensured the ultimate challenge to keep the vessel’s propulsion power below the 3,000 kW was met.
By using a MaK 6M32C, with an output of 2,999 kW, lesser competency for engine room crew is required than on comparable ships. Furthermore, fuel consumption and emission of harmful exhaust gasses are considerably lower.
An additional advantage of the Crossbow shape is the improved sea-keeping characteristics, leading to more comfort for seafarers and increased safety for ship and cargo in challenging weather states. A further benefit of the Crossbow is the covered forecastle deck, protecting the anchoring and mooring equipment.
However, it is not merely the Crossbow that has a positive impact on the low power requirements and low fuel consumption: to complement the optimised hull shape, special attention has been paid to the propulsion plant and the propeller design.
As a result, Furuvik has high propulsion efficiency with exceptionally low levels of vibration and noise in the accommodation. By placing the propeller in a nozzle even more thrust was generated.
The Finnish ice class 1A allows for sailing through broken ice. For improved cruising behind an icebreaker, the Crossbow is made slightly ‘blunter’ compared to previous versions.
Liquid Cement and Fly Ash
The sides of each of the four cargo holds are straight vertical flush bulkheads, while the cargo hold bottoms are sloped towards the collection points, into the transportation system at the ship’s centreline. As the sloped tank bottoms are integrated in the double bottom tanks, the vertical centre of gravity of the cargo in the holds can be kept relatively low when required, improving the ship’s stability.
Being able to carry cement as well as fly ash presented a challenging study to optimise the vessel, particularly it‘s stability, for both voluminous and weighty cargo. With a specific weight of 0.8 t/m3 for fly ash, the vessel’s loading capacity is limited by volume, while for cement (with a specific weight of 1.6 t/m3) it is limited by weight. Hence the importance of the ability to keep the centre of gravity low and also the requirement for a versatile layout of the ballast tanks.
At the ship’s centreline, between the starboard and port side holds, lie the channels containing the hearts of the fully automated transportation system. This transport system is based on fluidisation of powder by means of injecting compressed air, allowing the cement and/or fly ash mixture to be loaded and unloaded through a fully enclosed system, via pipes and chutes, thus dust-free for the environment.
Loading and unloading of cement or fly ash with this system is based on a pneumatic system, while loading can also (partially) be done mechanically by relying on forces of gravity. To avoid a blowout, the tanks are kept under vacuum during (un-) loading operations. To prevent dust flying around and penetrating everything, ample filter capacity has been provided.
In the implementation of the cement handling system on-board, Royal Bodewes collaborated closely with bulk material handling company, Ibau, from Hamburg. Pneumatic unloading is done through the specially designed (perforated) bottom, wherein air is blown into the cement and/or fly ash, after which it can be pumped over to a truck or silo. After unloading, the air is subsequently pressed out of the cargo with a cyclone. Loading through chutes is done in a similar manner and can be done at a speed of 800 tonnes per hour.
Because the ship is equipped to load very quickly, it was unavoidable to adapt the speed of the ballast system to maintain stability during loading. As a result of the use of superior pumps, Furuvik can de-ballast at a speed of up to 500 tonnes per hour. Furthermore, the vessel is fully prepared for the installation of a matching ballast water treatment system, as is mandatory for all vessels for which the keel was laid after the first of January 2017.
To ensure that the cargo sufficiently settles, releasing the surplus air, it is good practice for the ship to stay in port for around one day after loading ‘powder’ cargo. All four tanks are electronically monitored to verify whether the cement or fly ash locks into place, by measuring the height of the cargo’s top surface. When sailing away prematurely, the cement and fly ahs will still be liquefied to a certain extend and create a free-surface effect, which is detrimental to the stability.
Cargo Holds versus Tank Layout
The vessel features four cargo holds: two in a row on starboard and similar to port side. Between the two holds lies a cofferdam compartment, accommodating the two compressors for the cargo (un-) loading system. On main deck, above the cofferdam, is where the filter housings and the cyclone are to be found.
To enhance the stability, a significant number of ballast tanks in the double hull sides and bottom, as well as the bow section, have been made available for correcting the inclination and/or trim during loading and to decrease or increase the vertical centre of gravity depending on the type of cargo.
The high-capacity ballast pumps are located in the engine room, whereas the dedicated piping and valves are housed in the centreline tunnel.
The MDO fuel tanks are located against the forward bulkhead of the engine room. All other ‘engine room related’ liquids are stored in tanks around the engine room, whilst the aft most hull section also comprises fresh (potable) water, sewage and gray water tanks, most of which are related to the domestic machinery and equipment, providing facilities for the accommodation. To the stern on port and starboard side, there are two more ballast tanks.
The engine room has a very spacious layout and all components are easily accessible for maintenance.
A 6-cylinder MaK diesel engine, type 6M32C designed to run on marine gas oil, is the heart of Furuvik, providing 2,999 kW at MCR. As a result of the smart hull design, only a 6-cylinder version is required, instead of the usual 8- cylinder engine a ship of this size would need.
The power is transferred through a Renk single stage vertical Marine Reduction Gearbox type RSV-750 (main drive reduction ratio of 4,20:1), via a relatively short shaft, to the propeller. The Controllable Pitch Propeller (CPP), Cat type MPP1040, has a diameter of 3,600 millimetres. Running at 143 rpm, this propeller is optimised for efficient propulsion at a low rpm, with minimisation of pressure pulses. The gearbox has a Power Take Off (PTO) to a shaft alternator of 550 kW at 1500 rpm.
For steering and maneuvering, a Benes fishtail rudder with an extra slim profile is fitted. The special construction gives a high lifting force for the relatively small rudder. The rudder is operated by Rolls Royce Rotary Vane steering gear.
The bow thruster is a Verhaar Omega OFP (fixed pitch) tunnel thruster, driven by a Leroy Somer electric motor of 500 kW. Due to the improved hull shape of the fore ship, the length of the tunnel is very short, thus increasing the efficiency of the transverse thruster.
The electrical installation is designed in such a way that only the shaft alternator on the PTO is required whilst at sea. In addition, two Mitsubishi generators sets of 762.5 kW each and Mitsubishi emergency generator of 287 kW are provided. The size of the main sets has been calculated to match the demands of the ship’s load, plus the use of the compressed air units of the cement transportation systems.
The entire electrical system is designed and built by Alewijnse Marine Systems, while Wolfard & Wessels Werktuigbouw delivered the complete system engineering and installation of the engine room.
Mod Cons according to Scandinavian Standards
The superstructure is located aft, facilitating a modern and comfortable accommodation for eleven persons. All single berth cabins are air-conditioned and equipped with private sanitary units.
The wheelhouse forward area contains the T-shaped navigation console with all the required navigation, communication and ship control facilities. Both aft corners are home to the radio desk and chart table respectively.
The bridge wings are inside and each has a small control desk with relevant primary control facilities. All bridge communication and navigation equipment were delivered and installed by Radio Holland.
Below the wheelhouse is the officer’s deck, with a dayroom, bedroom and bathroom for the Master Mariner and Chief Engineer, including a generous office for the Master Mariner. One level lower, the boat deck, contains similar, though smaller, facilities for the second engineer, plus the first and second officer. The main deck accommodates the crew cabins and an office, along with technical spaces and the emergency generator room. The tween deck houses two cabins for the cook and a crewmember, a sauna and gym, as well as containing a provision storage, mess room, galley with pantry, laundry/changing room, the switchboard room and an engine room workshop.
Hoist the anchors
The Furuvik is equipped with two horizontal windlass installations with a double drum, gipsy and warping head on forecastle deck, for anchoring and mooring activities. On the aft deck, the vessel has two more horizontal windlasses, also with a double drum and warping head for mooring purposes.
At the stern, the required life-saving and rescue equipment was found. It consists of a free-fall lifeboat to the stern and a rescue boat on starboard side next to the superstructure on boat deck. Also on boat deck, more aft, are the inflatable life rafts, one on each side. This layout is completed with a deck crane for lowering and recovery of the lifeboat, recovery of the life rafts and other light lifting purposes.
Royal Bodewes philosophy
Situated along the Winschoterdiep in Hoogezand, The Netherlands, Bodewes Shipyards is a member of the Bodewes Group. The shipyard was founded in 1812 and focuses on designing and building ships according to market demands, based on the principles of quality, reliability, flexibility and Dutch craftsmanship.
The shipyard was awarded with the predicate ‘Royal’ in 2012. The Royal Bodewes philosophy is that the market dictates the configuration of ships, not vice versa.
Consequently, a changing market requires evolving designs to keep pace with the changes. Although based on a proven design, which is standardised in many cost-saving aspects, Furuvik is a good example of extensive customising to meet the customer’s requirements.
This article was previously published in Maritime Holland edition #2 – 2017.