news from grontmij
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Twin Fin– New Propulsion Systemfor the Offshore IndustryTRANSCRIPT
Volume 11, no. 1 | Denmark | April 2013
news from Grontmij
Twin Fin – New Propulsion System for the Offshore Industry
Efficient ships L-Class Upgrade for torpedo anchors New Handysize bulk carrier design New Ultramax bulk carrier design BEATER Fitted for Canadian Waters
Twin Fin – New Propulsion System for the Offshore Industry
During a compressed 2 months period from September 2012 Grontmij has, in collaboration with the joint venture partners Berg Propulsion, Sweden and Scandinavian Marine Group, Nor-way, developed a new heavy duty alternative to azimuth propulsion for Offshore Service Vessels working in harsh environments. The result was a presentation of our Scandinavian design: ‘Twin Fin Propulsion’ at the Annual Offshore Support Journal Conference & Awards in London in February 2013. Today diesel-electric propulsion systems in Offshore Service Vessels are most commonly equipped with rotatable azimuth thrusters driven by electric motors. This eliminates the need for rudder and stern tunnel thrusters, but makes the vessel more vulnerable due to the angle gears and other mechanical parts not being accessible from inside the vessel. Further, exploration in arctic areas calls for systems capa-ble of withstanding ice forces and performing ice breaking duties. In case of break down on azimuth thrusters, it is normally necessary to go in dry dock for repair.
Marine
The system is intended for Offshore Service Vessels working in Dynamic Positioning mode, but will also be a competitive alternative for other twin propeller vessels where noise and vibration requirements call for diesel-electric systems, such as seismic or cruise vessels. The Twin Fin Propulsion is also uncomplicated for retrofits on existing azimuth-fitted vessels where a short yard stay is made possible by the system prefabrication. The two separate propulsion units that substitute the azimuth thrusters consist each of a controllable pitch propeller mounted as normally seen on single screw vessels with aft bulb. Rud-der can be of high efficient flap type, where high manoeuvrability is required and tunnel thrust-ers, arranged in centre skeg, where e.g. dynamic positioning ability is required. Ice protection fins can be mounted on the twin fins as on single screw vessels as well as an ice knife behind the rudder. Inside, the system includes only one water-lubricated bearing, where the seal can be re-placed from within the hull. The short shaft has
couplings to the gear and the electric induction propulsion motor. As an alternative to a geared solution a permanent magnetic electric motor can be directly coupled to the shaft line. The compartment is easily accessible from in-side the hull, from where also the gear and electric motor can be removed. The system has been designed and analysed on Grontmij’s latest Flex90 – Arctic which is a high powered Offshore Service Vessel. The Twin Fin Propulsion has shown excellent results in overall performance. Obtained results from CFD simula-tions of the vessel with the Twin Fin Propulsion System show significantly higher total propulsive efficiency compared to the same vessel design with azimuth thrusters, a total 5% fuel saving still with improvement ongoing and a bollard pull increase of at least 6%.
More information
Bjørn Moving
Three of Maersk’s latest anchor handlers from Stralsund the ‘Leader’, ‘Launcher’ and ‘Lancer’ underwent a conversion, in the fourth quarter of 2012, for a Petrobras tender in Brazil involving deep water launching of torpedo anchors.
Main issue was installation of the ODIM-produced 200 ton. SWL Anchor Recovery Frame (ARF) making the torpedo anchor handling much more controlled without the tipping point effect when long items are launched over the stern roller. The ARF can lift the handling wire over a top roller 6.7 m. above deck and is flush with working deck in parked position. To ease the handling of the 120 ton torpedo anchors (5 in total each journey) the 600 m2 wooden part of the working deck was exchanged with a heavy steel composite deck and handling rollers alone adding 155 ton extra steel to the vessels. All three vessels have been equipped with two 170 ton line pull secondary winches each with capacity for 7000 m. / 76 mm. wire rope which implied installation of an extra top garage winch on ‘Leader’ and ‘Launcher’. Rig chain capacity was increased by converting two existing fuel oil tanks and a chain transfer system was established. Grontmij has delivered design draw-ings, delivery documentation including stability manual as well as assisting the 14 members of the Maersk team on site during the 45-day yard stay at Remontowa where the three vessels arrived with only few days interval.
L-Class Upgrade for torpedo anchors
Maersk Lancer at Remontowa Shipyard Poland
Anchor Recovery Frame (ARF) for launching of torpedo anchors
More information
Bjørn Moving
This newsletter is mainly dedicated to our Offshore Service Vessels (OSV). Grontmij has been designing OSV’s for the past 25 years, both newbuildings and conversions of existing vessels. Grontmij’s design, the Flex Supply, is a series of OSV’s ranging from 60 m to 130 m. As the name indicates the flexibility of the vessels represent the different services that apply for vessels operating in the Oil & Gas Industry. Late 2012 we developed an arctic OSV, the Flex Arctic 90, for services in arctic areas. When developing this vessel, we saw a need for a more robust propulsion system and we found that our Twin Fin Propulsion system could fulfil demands and require-ments for services in icy waters. The system is developed together with Berg Propulsion and Scandinavian Marine Group and has now been patented. The system is more robust and due to the shape of the fins, there is a fuel saving of at least 5% com-pared with traditional thruster propulsion systems and can of course also be used outside icy waters. At Grontmij we focus on fuel savings and efficient vessels and our new designs within Bulk Carriers, Seahorse 41 (41.000 DWT) and Seahorse 62 (62.000 DWT), are very fuel effi-cient with low fuel consumption, compared to existing vessels on the market. This is also valid for our new container feeder vessels in the range from 1600 TEU to 2800 TEU. I hope you will enjoy the reading of the articles.
Leif Jacobsen
Leif Jacobsen, Marine.
Efficient ships
Launching of torpedo anchors before installation of ARF
SEAHORSE 41 – (41,000 DWT) is our new Handy-size design and is based on same concept ideas as our SEAHORSE 35 and 375, but with slightly enlarged dead weight. The vessel size in the Handysize segment has gradually increased from below 30,000 ton and with our latest SEAHORSE 41 design, deadweight exceeds 40,000 ton. The principal dimensions of SEAHORSE 41:
The SEAHORSE 41 is designed to accommodate the new Green Engine Type from MAN Diesel, which is a MAN 5G50ME-B9.3. The new engine type has extremely long stroke, which in combi-nation with the enlarged NPT propeller provides very high propulsion efficiency. These features combined with energy saving device from Becker Marine result in very low fuel consumption. At design draught (37,000 DWT) and at 14.0 knots speed the fuel consumption is 19.9 ton per day (based on 15% sea margin and calorific value 42,700 kJ/kg). The EEDI is 14.4 % below the IMO baseline, which proves the high efficiency of the vessel. SEAHORSE 41 is laid out with 5 flush double skinned cargo holds, wide hatches and no hop-per tanktops, thereby ensuring easy access and storage of cargo in all cargo holds. Easy cargo
hold cleaning and short turn-around time is achieved by the complete flush cargo holds and effective cargo hold cleaning by portable wash-ing machines. Outlets of water and compressed air are arranged in all cargo holds at tanktop level. The washing water can be pumped to the washing water holding tank, ensuring that the cargo hold washing can be done alongside. The SEAHORSE 41 is also available in a wide hatch version with no wing tanks.
More information
Jan Kærgaard Lang
In order to follow up on the success on our SEAHORSE 35 and SEAHORSE 375 bulk carriers design, Grontmij have launched a new Handysize bulk carrier and a new Ultramax bulk carrier design.
New Handysize bulk carrier design
LOA 180.0 m
B 32.26 m
D 15.10 m
T (design) 9.75 m
T (scantling) 10.50 m
DWT (scantling) 41,000 ton
New Ultramax bulk carrier design
The principal dimensions of SEAHORSE 62:
The SEAHORSE 62 is designed to accommodate the new Engine Types from Wärtsilä, which are 5x62, 6G50 and 6G60. The engine types have extremely long stroke, which in combination with the enlarged NPT propeller, provides very high propulsion efficiency. These features combined with energy saving device from Becker Marine result in very low fuel consumption. At design draught (49,100 DWT) and at 13.0 knots speed the fuel consumption is 17.1 ton per day (based on 15% sea margin and calorific value 42,700 kJ/kg). The EEDI is 19.7 % below the IMO baseline, which proves the high efficiency of the vessel.
Seahorse 35 M/V Nina-Marie entering port Everglades
SEAHORSE 62 (62,000 DWT) is our new Ultramax design. The SEAHORSE 62 design concept is in many respects similar to SEAHORSE 35, 375 and 41. Ultramax is a fairly new bulk carrier segment which replaces the previously popular Supramax segment, of which Grontmij has also previously been very successful (DIAMOND 53).
LOA 199.9 m
B 32.26 m
D 18.50 m
T (design) 11.30 m
T (scantling) 13.40 m
DWT (scantling) 62,000 ton
SEAHORSE 62 is laid out with 5 single skinned cargo holds and wide hatches, thereby ensuring easy access and storage of cargo in all cargo holds. Outlets of water and compressed air are arranged in all cargo holds at tanktop level. The washing water can be pumped to the washing water holding tank, ensuring that the cargo hold washing can be done alongside. The SEAHORSE 62 is also designed in a ver-sion, with a deadweight decrease to 61,000 ton.
Easy cargo hold cleaning and short turn-around time is achieved by the complete flush cargo holds and effective cargo hold cleaning by port-able washing machines.
More information
Jan Kærgaard Lang
Publisher: G
rontmij · Sup
ervising editor: Leif Jacob
sen, leif.jacobsen@
grontmij.d
k Ed
itorial staff: C
aroline Autzen, caroline.autzen@
grontmij.d
k· Production: G
orm Larsen &
Zornig A/S.
Leif Jacobsen Director Marine
T +45 4348 4760
M +45 2723 4760
Peter Smith BendtsenNaval Architect
T +45 4348 6876
M +45 2723 6876
Bjørn MovingNaval Architect
T +45 4348 6816
M +45 2723 6816
Søren Schnack Naval Architect
T +45 8220 3594
M +45 2723 3594
Jan Kærgaard Lang
General Manager, Shanghai
T +86 21 6145 4901
M +86 137 6471 0648
Contact Marine
GrontmijGranskoven 8
DK-2600 GlostrupT +45 4348 6060F +45 4348 6660
www.grontmij.com
BEATER Fitted for Canadian Waters
Maersk Beater underwent a conversion, in the fourth quarter of 2012, for a Statoil charter involving semi-sub rig support off the coast of Canada. This includes anchor handling, towing, supply duties, passenger transport, stand-by and ice management. The vessel flag was changed to Canadian, deck re-arranged and equipment installed according to Canadian stand-by rules for 185 survivors and the ice class was upgraded to 1C. The ice class upgrade was obtained by ex-change of both plates and supporting structure in fore ship ice belt region and by adding ice frames in the mid and aft region. The total of 86 ton added new steel involved hot work in 24 side tanks. Grontmij has delivered design drawings, de-livery documentation including stability manual as well as assisted Maersk on-site during the compressed 45-day yard stay at Fayard.
More information
Bjørn Moving
Built in of ice reinforcement at Fayard Denmark
Maersk Beater in dry dock at Fayard Denmark
Built in of ice reinforcement at Fayard Denmark