FKAB provided the original vessel design and technical conversion documentation

The FKAB Marine Design L21 ammonia carrier Shenghang Yongle, has been converted for ship-to-ship liquid ammonia fuel bunkering. Led by Jiangsu Andefu Energy Development, FKAB together with cargo handling supplier Gloryholder provided the technical drawing documentation for the conversion. The vessel is now the world’s first operational ammonia bunker vessel and has received the first ammonia bunkering class certificate.

The achievement represents an important step in the development of the infrastructure needed to support ammonia as a marine fuel. While several ammonia bunker vessel projects have reached the design, feasibility or construction stage, the Shenghang Yongle has now progressed into operational readiness.

Originally designed as a flexible liquefied gas carrier, the vessel has been upgraded from a conventional ammonia carrier into a dual-purpose vessel capable of both transporting liquid ammonia and delivering it as fuel through ship-to-ship bunkering.

A versatile platform for ammonia transport and bunkering

Shenghang Yongle is a 5,500 m³ semi-refrigerated and semi-pressurised liquefied gas carrier. The vessel was designed by FKAB, built by China Merchants Shipbuilding Industry Dingheng shipyard and is managed by Shenghang Shipping Co., Ltd.

Designed for unrestricted navigation, the vessel can carry several liquefied gas cargoes, including ammonia, LPG and vinyl chloride monomer. Its cargo tanks have a minimum design temperature of −48°C, and the vessel is equipped with two low-temperature reliquefication systems.

These characteristics provided a strong technical foundation for the subsequent conversion. The vessel’s existing cargo containment and handling capabilities could be adapted to meet the additional requirements associated with transferring ammonia as a marine fuel.

From cargo carrier to bunker vessel

Jiangsu Andefu Energy Development led the conversion and certification process in close cooperation with China Classification Society, while FKAB together with Gloryholder prepared the technical drawing documentation required for the conversion. The overall work included modifications to the bunkering system, development of operating procedures, risk assessments, and the establishment of safety and emergency-response arrangements.

Particular attention was given to the challenges associated with ammonia, including toxicity, material compatibility, low-temperature operation, leak detection and risk control during bunkering.

Closing a critical infrastructure gap

Ammonia is regarded as one of the most promising potential zero-carbon marine fuels when produced using renewable energy. Its wider adoption, however, depends not only on ammonia-capable ships but also on a safe and reliable supply chain, including production, storage, transport and bunkering.

The lack of operational ammonia bunkering vessels has been one of the important gaps in this chain. The conversion of the Shenghang Yongle demonstrates how an existing ammonia-capable gas carrier can be developed into a practical bunkering asset.

Designed for today, adaptable for tomorrow

For FKAB, the project demonstrates both the long-term value of designing vessels with operational flexibility in mind and the importance of maintaining detailed knowledge throughout a vessel’s lifecycle. Having developed the original vessel design, FKAB was able to support its next stage by preparing the technical drawing documentation for the ammonia bunkering conversion.

Shenghang Yongle was designed and built as a capable, versatile working vessel. Its conversion into an ammonia bunker vessel shows how robust naval architecture, adaptable cargo systems and carefully developed conversion documentation can help turn the marine energy transition into operational reality.

We congratulate Jiangsu Andefu Energy Development, Shenghang Shipping, China Classification Society, Gloryholder and all other parties involved in achieving this significant industry milestone.

FKAB Marine Design are present at Posidonia Exhibition 1-5 June.

We are part of the Stand no. 3.315 arranged by IntraMare.
Make sure to stop by us, Martin Gombrii, Andreas Hagberg and our representative in Greece Konstantinos Fakiolas, to discuss efficient and environmental friendly ship solutions.

Mari-Tech 2026, 12-14 May

This year Mari-Tech is held in Victoria BC, Canada, and FKAB is present.

Stop by FKAB at Booth 53 and discuss efficient ship design.
It can be anything from conversions to Newbuildings, low energy consuming ship solutions, green technology like fuels including batteries, Wind Assisted Propulsion and last but not least excellent hull forms that perfectly fits your needs.

The FKAB T61, 7000 DWT Stainless Steel Tanker, is ready for the future.

Wind-assisted propulsion is emerging as one of the most promising energy-saving technologies in shipping. However, successfully integrating wind propulsion is not simply a matter of installing sails. It requires a vessel designed from the outset to operate efficiently with wind-assisted propulsion.
The T61, a 7 000 DWT stainless steel chemical and product tanker has therefore been developed with wind integration as a core design principle. The concept combines high operational efficiency today with flexibility to adapt to future energy solutions.

Efficient by design
The vessel features an optimized hull form with FKAB’s F-Bow, improving seakeeping in rough conditions while reducing resistance. This is particularly important for vessels operating with wind propulsion, where improved behaviour in waves directly influences overall performance.
Even without wind-assisted propulsion or other energy-saving devices, the vessel demonstrates strong inherent efficiency. At 11.5 knots, the T61 concept consumes approximately 7 tonnes of fuel per day at 80% MCR, including 150 kW electrical load and a 15% sea margin.
The preliminary EEDI performance is well below the IMO requirement, even when calculated without sails or other energy-saving technologies and including a five percent engine maker tolerance. Depending on fuel choice, the attained EEDI ranges between 6.72 and 8.76, compared with a required value of 15.08, providing a significant margin for future regulatory developments.

Wind-assisted propulsion
The design includes structural preparation for wind-assisted propulsion systems such as suction sails, rotor sails or wing sails. Two sails are expected to provide a combined mean saving of approximately 290 kW, corresponding to roughly 1.2 tonnes of diesel per day.
Because wind propulsion performance is highly dependent on operating conditions, FKAB performs advanced wind studies, analysing wind statistics, trading routes and operational profiles. These studies determine whether wind-assisted propulsion can deliver meaningful savings on specific trades and help identify the most suitable sail technology.

Hybrid propulsion and battery capacity
The propulsion system is designed as a hybrid arrangement supported by a substantial battery installation. The vessel is equipped with 6 MWh of battery capacity for peak shaving, UPS functionality and operational flexibility. Additional space is reserved for a further 3 MWh of battery capacity, allowing the system to expand to 9 MWh as operational needs or regulatory requirements evolve.

Future-ready flexibility
With preparation for wind propulsion, hybrid power integration and future fuel solutions, the T61 concept provides shipowners with a vessel platform that combines efficiency today with adaptability for tomorrow.
When wind becomes part of the propulsion system, naval architecture matters more than ever.
Link to T61 Reference & Onepager

Xiamen Shipbuilding Industry Co., Ltd. (XSI), China, delivered on Thursday 08 January the first vessel of  six MR sized ships for German Tankers.

Delivery ceremony of “SEADEVIL”, the first vessel of six sisters for German Tankers, was held on January 08.
This FKAB T67 MR tanker Newbuilding project is of 41 000 DWT and with a bit different main particulars, for increased performance, than we are used to see on MR tankers.
FKAB marine design have delivered both Basic Design and Detail Design, through our FKAB Sweden and FKAB China offices.
More details, pictures and the news article from the Yard are found further down.

The FKAB T67 is a Tier III product and chemical tanker (IMO II & III) vessel, and will
be compliant with future environmental regulations but will also apply innovative eco-technology for
your next generation of green ships and it is optimized for worldwide operation.

Special attention is taken to optimize hull lines including the patented F-bow resulting in
energy savings and reduction in CO2 emission over the ship’s life. The vessel is designed
with high standard European accommodation and equipped with, battery pack and shore
connection for supply of green electricity during port operation.
All pipes except the manifold are located inside the closed pipe trunk, which is running from aft
to forecastle.

The propulsion system consists of one medium speed engine coupled to a contrallable pitch
propeller and a shaft generator. The shaft generator will also be used as ’take me home’ and will
be connected to the electric net via a frequency converter allowing variable speed of the engine /
propeller for both PTO / PTI and PTH. In port during discharging the main engine will be used as a
generator by remote operated hydraulic clutch that disconnect the propeller shaft from gear.

Main Dimensions:
Length over All, 199.00 m
Beam, 32.20
Draught Design, 11.10
Draught Scantling, 12.00
Deadweight at Design Draught, 41 000 DWT
Design speed, 13 knots
Preliminary EEDI, 3.93
Ice Class 1B

Xiamen Shipbuilding Industries News Article

On the afternoon of January 8, 2026, Xiamen Shipbuilding Industry Co., Ltd. (XSI) successfully delivered the first 41,000 DWT oil and chemical tanker “SEADEVIL”，built for German Tanker Shipping (GTS) Company. Mr. Ulrich Niebusch, Director of GTS; Mr. Chi Shaoguang, Manager of DNV Guangzhou Branch; Mr. Lv Bin, General Manager of FKAB China; Mr. Huang Xinqiu of Haidely；Mr. Lin Qin, Chairman of XSI; Mr. Wang Nenghua, General Manager of XSI; Mr. Gao Dengpan, Deputy General Manager of Fujian Chuanzheng Shipbuilding Industry Co., Ltd.; and other relevant leaders and representatives attended the ceremony, jointly witnessing this milestone moment.

As a world-class, top-spec MR-type oil and chemical tanker, SEADEVIL has overcome a number of core technological hurdles throughout its construction. It has achieved breakthroughs in propulsion systems, extreme environment adaptability, and green-intelligent integration, which not only demonstrates XSI’s robust prowess in smart manufacturing, but also fills multiple domestic gaps in high-end shipbuilding technologies, facilitating the high-end transformation of China’s shipbuilding industry.

Domestically Pioneering Controllable Pitch Propeller: Conquering Ice Zone & High-Efficiency Propulsion Challenges

One of the core technological breakthroughs of this vessel is that it is the first domestic MR-type oil and chemical tanker equipped with a controllable pitch propeller system featuring real-time pitch and speed optimization. The R&D and integration of this system demand extremely high precision in matching hull lines, power output and operating conditions. It achieves dynamic pitch optimization, boosting propulsion efficiency by over 10% while overcoming the challenge of seamless switching between low-speed ice-breaking in ice zones and normal navigation.

Designed to operate in extreme cold conditions of -30℃, the propeller is reinforced in accordance with ice zone specifications, and the ice belt area of the hull is also strengthened to ensure ice resistance—thus filling the domestic gap in MR-type oil and chemical tankers capable of navigating extremely cold ice zones. Equipped with an intelligent power management system, the vessel can adjust propeller pitch and speed in real time, seamlessly switch between PTO/PTI/PTH modes, cut fuel consumption by 8%, and has been granted the DNV Smart Ship class notation.

Green Power Innovation: Methanol-Ready & Low-Carbon Configuration

Green Power Integration was a key focus of this project’s technological efforts. The vessel features a methanol-ready design, alongside a 402 kWh lithium titanate energy storage battery to guarantee uninterrupted emergency power supply. When berthed, it can connect to medium-voltage shore power; coupled with a shaft generator and waste heat recovery system, it fully complies with the latest IMO environmental regulations, with emissions far below international limits.

High-Precision Liquid Cargo System: Compatible with 14 Chemical Types

The design and construction precision of the liquid cargo system is critical to navigation safety, presenting significant technical challenges. The vessel adopts a double bottom, double hull, and epoxy-coated cargo hold design, boasting 12 independent cargo oil tanks and 2 slop tanks. Each tank is outfitted with an independent pump set and monitoring system, enabling simultaneous loading of 14 chemical types and completion of multi-type loading/unloading operations in one day. Its stowage flexibility ranks among the world’s highest, complying with OCIMF and IBC codes.

The successful delivery of “SEADEVIL” is a vivid embodiment of XSI’s core philosophy of “Innovation-Driven, Quality-Leading, Customer-Centric” and marks a key milestone in the company’s product transformation and upgrading journey. Moving forward, building on this delivery success, XSI will continue to advance the upgrading of its product structure towards high-end, green, and intelligent development. Expanding from high-end oil and chemical tankers to dual-fuel ro-ro ships and other diversified high-end vessel portfolios, it will leverage technological innovation to break industry barriers and strive to establish a benchmark for “Xiamen-made” high-end vessels.