Growing fleet provides new challenges

LNG carriers typically have trading lives much longer than most commercial cargo carrying ships, often operating for as long as 40 years. During such an extended period technology advances and commercial requirements and new legislation mean that the lifecycle management of LNG carriers is particularly important if they are to remain legally compliant and technologically and commercially efficient.

For many years nearly all LNG carriers were owned and operated by the oil majors that used their services or by a handful of major shipowners. However, more LNG carriers have recently been built by independent owners, and their technical and crewing management contracted to in-house or third-party shipmanagers. These companies play a key role in the lifecycle management of the vessels and in advising the shipowners what upgrades are necessary to meet their operational requirements and maintain the vessels to the high standards that are necessary and characteristic of the LNG shipping sector.

Bernhard Schulte Shipmanagement (BSM) is among the leaders when it comes to LNG carriers. Chris Clucas, responsible for LNGCs for the company, said that BSM provides crew management services for 20 LNG carriers, and full technical and crew management for two vessels owned by Thenamaris LNG in Greece. The latter two ships have diesel-electric propulsion and were recently delivered by Samsung Heavy Industries in South Korea. Each has a TGZ Mk III cargo containment system.

“We have several projects in hand that we foresee will lead to an expansion in our technically managed LNG fleet,” Mr Clucas told LNG World Shipping.

Mr Clucas said that the main challenges specific to LNG carriers concerning their propulsion, cargo containment and cargo handling systems are often related to the complexity of the design, especially in the case of the integrated control systems. “The vessels we manage were very well built in a top class shipyard under the supervision of highly experienced team,” he said, “so the few actual problems experienced have been quite minor and have not impacted the ship’s operations.”

One potential problem facing LNG ships is that as the global fleet increases, the availability of drydocks able to carry out maintenance and repair work on such specialised vessels could become limited, even though LNG carriers still comprise a small percentage of the global fleet and dry dock intervals have increased.

Mr Clucas commented: “Many LNGCs have the same types of specialised machinery, such as steam plants, gas/oil diesels, submerged cryogenic cargo pumps, and cargo compressors. So it is important to organise dockings well in advance to ensure that specialist technicians are available as and when required. In this respect, many LNG charters require notice periods of up to 12 months for maintenance of ships on project business, so it is possible to plan dockings in an orderly way.”

With drydock intervals extending, the use of shipboard staff to maintain equipment and effect repairs becomes more important. Mr Clucas said that BSM’s normal policy is to use the ship staff to the maximum possible extent to maintain, troubleshoot and repair the equipment. “The staff on board are highly trained and experienced, plus they have the day-to-day familiarity with the systems,” he said. “In this respect LNGCs are no different to the rest of the fleet managed by BSM.”

The growing LNG fleet has posed some challenges in terms of recruiting and retaining skilled shipboard and shore-based staff with the necessary specialist qualifications and experience. Mr Clucas said the LNG carriers are in demand among seafarers: “Our normal policy is to train and promote people from within our own resources, to the maximum extent possible, as our experienced staff are completely familiar with BSM policies and procedures.

“There can, however, be problems in complying with the different experience matrices applied by various charterers. BSM will not take on the management of additional vessels unless we can provide qualified and experienced staff to operate them to the client’s satisfaction.”

Providing for the relatively long trading lives of LNG carriers poses particular challenges. Mr Clucas said: “In our experience with older vessels in general, the major problems arise from obsolete equipment, which simply has to be replaced when spares or repair are not economically viable or sometimes not available. Likewise the condition of the hull steel, especially in the ballast tanks, can influence the viability of any life-extension project. But LNG carriers are not unique in this respect.”

Other particular aspects of LNG carriers are that the cargo spaces benefit from the dry, non-corrosive and cryogenic nature of the cargo, so deterioration of the cargo containment systems is not the same problem it is on some other ship types. And, if the cargo boil-off is the main fuel, the propulsion system benefits from the clean alternative to heavy oil.

These features mean that LNG carriers are good candidates for conversion to floating storage or similar uses. With new, fuel-efficient vessels entering the world LNG fleet, it is likely that 2015 will see a number of older ships withdrawn from trading and converted, despite being maintained in excellent condition.

Belgium-based Exmar is a leading owner and operator of LNG and LPG carriers. Its Exmar Ship Management (ESM) unit provides technical management services for the owned fleet but also for third party LNG and LPG shipowners.

ESM has 15 LNG carriers under technical management for four owners. The vessels include five conventional LNG carriers, eight LNG regasification vessels and two floating storage and regasification units (FSRUs). All are fitted with membrane type cargo containment systems, while their propulsion systems can be steam turbine or dual-fuel diesel-electric.

Exmar handles all technical and crewing management for vessels LNG Lerici and LNG Portovenere of LNG Shipping, a fully owned subsidiary of Italian energy major ENI. It has an Italian superintendent and Italian deputy marine superintendent based in Italy to provide technical services and has adapted its shipmanagement system to meet ENI requirements.

ESM managing director Marc Nuytemans told LNG World Shipping: “Exmar Ship Management is interested in entering into long-term relationships where the company’s expertise and innovative approach to shipmanagement can add genuine value and contribute to the customer’s business model.”

ESM’s LNG fleet manager said that the technical challenges in lifecycle management vary according to the specific characteristics and machinery of each vessel. Ships with steam turbine propulsion, which many LNG carriers still use, do not require much maintenance and use proven technology for many years, though with a relatively low level of efficiency. The high-pressure boilers mostly operate on gas and do not need much maintenance beyond regular classification inspections.

“The latest generation of boilers has been designed to operate at the limit of their capabilities in order to increase efficiency,” he said. “Boiler components such as economisers and superheater pipes operate at higher temperatures, so we do employ sufficient methods which anticipate repair needs during scheduled drydocks in order to guarantee constant availability.”

For (DFDE) systems, which have become more popular among owners as they increase fuel efficiency, the main challenge is that there is a lot of hi-tech equipment involved and a lot of electronics. ESM’s LNG fleet manager said: “Maintenance needs to be performed during drydocks by service engineers and, additionally, the systems are more complex in terms of troubleshooting onboard for the ships’ engineers and automation engineer.

“Performing maintenance onboard during a voyage on the electric propulsion system or the dual-fuel engines presents a challenge as both are high-tech systems and are very sensitive. The suppliers of these engines have experienced a boom period in terms of demand and, consequently, there are quite a few teething problems with these engines that need to be addressed.”

Normally the vessels have enough redundancy onboard for at least one engine to be taken out of service while the others are capable of ensuring propulsion.

“The challenge faced with these propulsion systems is that much more assistance is required from service engineers,” ESM’s LNG fleet manager said. “Not all companies have service engineers available when needed.

“Service engineers are very often required to solve problems, and suppliers require more time to train their service engineers. This can be a challenge when the technicians that come onboard still need time to become fully familiar with the products. Workload in the engineroom can also rise due to the number of cylinders on board.”

Remote control access to the engine suppliers using the ship’s internet connection is becoming a new development may reduce the time to repair and generate cost savings in terms of travel time for engineers.

Supply of electronic spare parts can often be a challenge. “At ESM an automated supply chain system is being designed using bar codes for spare parts with regular inventories using rugged tablets on board to ensure availability,” ESM’s LNG fleet manager said. “In addition we are developing a comprehensive new online maintenance system which will further improve efficiency.”

He added that major shipyards now have cryogenic workshops to cope with the increasing number of LNG vessels, and repairs to LNG vessels require an increasing number of service engineers. But most work carried out at shipyards is similar to other ship types.

He said that most LNG ship managers are focusing on fine-tuning their computer-based maintenance programmes. “This requires more and more involvement from ships’ staff in performing maintenance while the vessel is in operation. Staggering running hours in terms of operation will permit some maintenance jobs to take place later during the drydocking period.

“LNG vessels are costly and usually built for a lifetime of 30-40 years. A master maintenance plan is an absolute must to guarantee this lifespan. Together with the owners, ESM has developed a master maintenance plan that takes into account all upgrades and renewal of vessel equipment at their respective anticipated lifetimes. It allows owners to properly prepare their upgrade and maintenance budgets throughout the lifecycle of the vessel.

“With the increasing array of electronics present on board LNG vessels, operators are faced with components and systems with a limited lifetime as suppliers are continuously improving them with the consequence that parts supply is available for a limited time period only.”

ESM is implementing condition-based monitoring as an efficient and effective tool that permits operability while ensuring that most of the maintenance work takes place during drydock. “Repairs that can be performed by sea staff will still be carried out by them but we see a tendency towards either deploying riding squads or shore gangs. Many companies are also looking into service agreements with different suppliers to maintain their equipment, mainly for the hi-tech electronic equipment.”

He said that ESM selects crew at the level of cadets and junior officers and then trains and develops their careers, which ensures that it has not faced any shortage of the engineers it needs.

Conversion projects are a major part of ESM’s work as part of its management of FSRUs. “Each regasification port has different requirements in terms of send-out capacity, regasification method, open or closed loop, efficiency, environmental requirements, etc.

“We are currently involved in modifying five FSRUs this year. The modifications include adding four dual-fuel engines to a steam turbine vessel, adding a boiler to a steam turbine vessel as an extra heat medium, and increasing cargo tank pressure modifications.” 

Keppel wins FLNG conversions

Keppel Shipyard in Singapore has secured a second floating liquefaction vessel conversion contract from Golar LNG. This follows shortly after securing the first such contract. Following the contract to convert the LNG carrier Hilli Keppel will also covert Gimi. Both Moss LNG carriers are being converted into FLNGVs.

Michael Chia, managing director marine & technology of Keppel Offshore & Marine, said: “Together with Golar LNG and our partner Black & Veatch we are confident that FLNGV conversion solutions are the answer to a need to bring small and mid-scale LNG suppliers to market in a more timely and cost efficient manner.”

Keppel is providing the design, detailed engineering and procurement of the marine systems and all conversion-related construction services. Black & Veatch will provide design, procurement and commissioning support services for the topsides and the liquefaction process utilising its established Prico technology. The project will take about 33 months to complete following the formal notice to proceed in 2015.

The Gimi conversion contract is the first of two options included in the original contract for the Hilli, so that one option to convert a further unit is still outstanding.

Teekay newbuilds reduce lifetime costs

According to Teekay LNG its latest newbuild vessels, installed with gas fuelled ME-GI engines, will generate savings of over US$25,000 per day compared with equivalent dual-fuel diesel-electric vessels. Reduced boil-off gas with reliquefaction will prevent LNG loss. The reduced engine complexity will also lower operating costs and increase reliability. Teekay LNG has 15 new vessels on order for delivery between 2016 and 2020. “Long-term contracts with oil and gas majors mean that vessel reliability and performance is crucial,” the company said.

A new lease of life

A pair of LNG carriers that are over 35 years old have recently secured new employment in a demonstration of the longevity of LNG carriers and the importance of associated lifecycle management.

The 1978-built 126,400m³ LNG Leo, operated by General Dynamics in the US, was contracted to carry a 100,000m³ part cargo from Rotterdam to FSRU Toscana in Italy after having been inactive at the Navantia yard in Spain.

Two sisterships LNG Gemini and LNG Virgo have also been lined up for a return to active service having been laid up in Spain and the Philippines, respectively, for more than 12 months. They will be brought back up to operational condition at the Spanish yard. The trio were part of an original eight-ship series whose long-term charters ended in 2011. The other five ships have suffered varying fortunes. One is still trading, three have been or are being converted into floating storage units and one has been scrapped. LNG