Register for a free trial
LNG World Shipping

LNG World Shipping

Opinion: What will push LNG shipping towards condition-based maintenance?

Thu 23 Jun 2016

Opinion: What will push LNG shipping towards condition-based maintenance?
CBM aims to break the periodic maintenance cycle and to perform it only when necessary (credit: MMHE)

Exmar technical superintendent Kjell Wouters

I’ve been involved in implementing condition-based maintenance (CBM) on board the Exmar Shipmanagement (ESM) LNG fleet since it started, in 2012. From the client side, what will push LNG shipping towards CBM is its need for absolute reliability.

In the case of floating storage and regasification units (FSRUs), continuous operation is the priority, as many are permanently berthed on location. A breakdown can cause trouble for the client, in serving energy suppliers, power stations and so on.

Cost effectiveness is of course an additional driver for CBM; reliability goes hand-in-hand with reducing the overall operating expenditure.

I was involved in the first pilot projects on board two LNG FSRUs, one in Kuwait and another in Bahia Blanca, Argentina in 2012. We tried out two candidate suppliers over a six-month period on each vessel to test instrument effectiveness and quality of data reporting, selected the most suitable provider and then set out a budget with the owners to implement CBM across the fleet.

Rather than allow that supplier on board to gather data, we purchased the equipment ourselves and trained our crew to make the measurements, then emailed the data to the supplier, deploying a third engineer on every vessel to train his colleagues.

We rolled out the CBM programme across the fleet of 10 LNG regasification vessels and carriers in 2013-2014. We were able to reduce the number of incidents that occurred shortly after a scheduled overhaul or replacement of equipment, where the equipment itself did not require any handling.

By monitoring the equipment at the right time, we could continue to operate it for a given period rather than perform an unnecessary overhaul, saving time and money. It has also allowed our crew to focus on improving operations for our client in other areas on board.

By monitoring the equipment in this way, we have also prevented many failures – by fixing a loose coupling or bearing before it breaks down.

One of our biggest challenges rolling out the CBM programme was to get initial buy-in from our crew. With so many years of experience on board these LNG vessels, our seafarers were accustomed to resolving technical issues that they had detected using sound, temperature change or changes in the vessel’s operational behaviour.

We were able to demonstrate that analysing and measuring the data would benefit everyone, and this was due in part to the supplier, which made no errors during the two-year roll-out in identifying whether or not to repair or replace a piece of equipment. This helped us to convince our engineers that we could save them time – using facts rather than arguments.


GE Marine Solutions president and chief executive Tim Schweikert

CBM aims to break the periodic maintenance cycle and to perform maintenance only when it is required. It is an alternative approach to planned routine maintenance, which can be implemented in such a conservative manner that parts are replaced long before they reach their end of useful life, and can fail to anticipate unexpected, early life failures, which can halt operations.

Modern software analytics is beginning to deliver the promise of CBM. At GE, we use SmartSignal analytics to predict the future condition of assets, allowing companies to monitor vessels in real-time, to record and analyse the history of their operations and maintenance activities and to search for anomalies.

SmartSignal can give early warnings when an asset is exhibiting off-standard behaviour, identifying problems before they occur – which can help to defer maintenance. The reduced downtime for an LNG carrier translates into significant savings in unplanned dry docking and can bring in revenue streams.

Despite the benefits of CBM, it also encounters challenges for implementation. Access to data is the key enabler for CBM. However, one crucial challenge that the industry must address before data can reach its full potential is the continued collection of data in silos.

Key stakeholders – vessel charterers, owners, operators and builders – can create levels of complexity when it comes to data sharing. Now, each party possesses its own data. Reluctance to share data and ambiguity in ownership present a barrier to realising the benefits of the digitalisation of the industry.

In data analytics, by going alone, you are going nowhere. That is why GE is collaborating with major players and why GE’s SmartSignal has been designed to be open source – it can run analytics on energy assets, whether or not these are GE equipment – to break down silos and demonstrate that collaboration can drive improved outcomes across industries for years to come.

Gaining insights to initiate CBM is another challenge that requires enhanced computing capability. Vast resources are needed to store, harmonise and analyse the data, which, in turn, requires immense investment, software expertise and deep knowledge of the sector.

GE employs more than 1,200 software engineers to help the industry embrace the digital transformation and harness the power of data. GE has also created Predix, the world’s first cloud-based platform for industrial application, to act as a nerve centre for software development and to provide powerful, consistent and secure support for the solutions.

One way in which the LNG industry differs from other marine sectors is that vessels generally follow the same route and share highly similar profiles. The digital solution that enables CBM will not require a high level of customisation, meaning its practice and benefit are highly repeatable and scalable across the fleet.

In the marine industry, maintenance management through condition monitoring and diagnostics is relatively immature in comparison with, for example, the manufacturing industry. The marine industry is risk-averse and customers want to be reassured before implementing the solution.

However, our customers recognise the value of CBM and digital solutions in general. We are working with early technology adopters to apply our digital solutions in the real world. Once the value is demonstrated, the solution can be quickly applied to a large volume of ships, driving improved outcomes across LNG shipping for years to come.


InterManager secretary-general Kuba Szymanski

First, let’s talk about floating storage and regasification units (FSRUs). The majority of InterManager members who have FSRUs do have condition-based maintenance on board.

That’s logical. A traditional shipping approach would repair equipment when time-based overhaul (TBO) calls for it – but when you have an FSRU, a breakdown is the last thing you want.

In order to prevent this, condition-based maintenance should be standard practice rather than a matter of waiting until time comes to carry out maintenance.

Let’s not be too hasty though, condition-based maintenance is quite complicated and the capabilities to do it effectively can be tricky to execute.

Many of the maintenance plans written by manufacturers are based upon the worst-case scenario and not necessarily for a marine environment, therefore there may be a considerable amount of slack in the TBOs if run under optimum conditions or run infrequently. This would be one of the main benefits of a condition-based maintenance plan.

We must be aware that owners seem to be working to short time scales, and condition-based maintenance just cannot deliver on a short-term basis.

The main engine manufacturers are regularly offering advice concerning extending the TBO for main components. Generally they will maintain the nominal overhaul interval in their maintenance plan, but provide recommendations for additional inspection that may allow the TBO to be extended.

There is always a sentence in these plans indicating that overhaul intervals may be reduced or extended based upon operating conditions, together with the results of physical inspection – which is essentially condition-based maintenance.

As we are seeing, only for FSRUs – for which stoppages cost a lot of money – is condition-based maintenance being considered. Members of InterManager have reported that they actually perform a lot of condition-based monitoring already, although this is sometimes forgotten, including:

  • Bunker analysis
  • Lube oil analysis
  • Cylinder oil scrap-down analysis
  • Boiler and freshwater analysis
  • Engine performance analysis (snapshot and in real time)
  • Shock pulse/vibration analysis
  • Physical inspection/measurement
  • Bearing temperature monitoring
  • Impressed current cathodic protection and marine growth protection system
  • Logging/review
  • Hull stress analysis
  • Containment system (IS and integrated bridge system) monitoring
  • Insulation testing

Based upon the maintenance package agreed with the engine maker, they can carry out performance analysis in real time or companies can provide them with recordings at agreed intervals. Therefore it should be reasonably simple to implement a condition-based maintenance plan with this level of monitoring.

There is quite an involved administrative process managing the condition-based maintenance plan. However, this should be offset by reduced unnecessary maintenance and fewer equipment failures.


Wärtsilä general manager service agreements Tage Klockars

Wärtsilä has condition-based maintenance service agreements with 11 or 12 LNG carrier owners that cover some 70 LNG carriers. Companies that use our CBM technology include Dynagas, Bonny Gas, Maran Gas and GasLog. We plan their maintenance planning, co-ordinate parts and manpower and everything relating to that.

We cluster maintenance in a smart way to reduce vessels’ down-times over a longer period. These vessels have four or five engines on board and we aim to perform maintenance while they are at sea, rather than forcing a stoppage, to reduce time spent drydocking. CBM allows us to introduce remote troubleshooting on demand.

The challenge is to persuade LNG shipowners of the benefits of condition-based monitoring. These sophisticated ships incorporate a high level of new technology and software, and because gas is a relatively clean fuel, LNG carriers suffer less wear and tear than vessels using heavy fuel oil.

Our strategy to grow this business has been to secure classification society approval for our CBM concept – notably with DNV GL, ABS and RINA.

Rather than do everything according to the manual we extend the timeframes – doing less work on board, or postponing certain maintenance requirements to bring cashflow benefits to the owner – which means less work, less hassle and more co-ordination.

The important thing, we feel, is that this is a class-approved system. This is a competitive field – but very few players have secured that approval.

Time is of the essence and the faster we can offer that support, the better. These systems detect problems and our customers are able to call us 24 hours a day to speak to a specialist who can solve the operational issue.

Data makes a lot of things possible; we are analysing and benchmarking ships’ data. We are also monitoring the condition of 75 thrusters to match their maintenance to charterer requirements – using CBM to fit around the customer’s needs, reducing major stoppages or extending the maintenance interval.

The fact that LNG carriers are expensive and technically advanced is an enabler for condition-based maintenance. We have achieved a success rate of some 88 per cent with our LNG customers, in terms of extending for another year the deadline for major maintenance.

We can also step in to prevent stoppages when problems occur. In one case, off West Africa, our remote systems detected that a GasLog LNG carrier newbuilding had a problem with its software systems that prevented the ship’s engines operating in gas mode.

The crew needed help to identify the malfunction and to correct the settings. Our remote-support specialist logged in to the vessel’s control system and analysed the equipment’s performance.

The specialist worked with the onboard service engineer and crew to identify incorrect settings, which prevented the ship having to return to shore and to pump back its gas, which would have cost a lot of money. We had to fix the problem quickly – and did so within eight hours.

In proving that our customers can avoid major capital ingress in this way, we expect CBM demand to grow. However, we have also put together what we call the Wärtsilä Genius services team to look more closely at ship efficiency, combining this with CBM.

Over time, the efficiency of engines or of propulsion goes down – it takes more fuel to maintain sailing speeds. So now, we are looking also at efficiency-based maintenance, developing data to predict when it is most feasible, economically, to resolve these issues, which means developing smarter analytics tools.

There’s a lot of talk about real-time data – about streaming data live from the ship. But with CBM and efficiency prediction tools, you eliminate the need to super-stream live data. We can use duplicate screens on shore, or cloud-based systems, to eliminate large transfers of information.

We are testing this on one LNG carrier at the moment, using the system to measure propulsion efficiency using a meter on the propeller shaft to measure torque and thrust. The back office is monitoring this with its analytics tools.

How much data you have, how much you need to make the correct decisions – these are two very different things. Our asset performance optimisation team is working on this and we hope to launch it globally later this year.

Recent whitepapers

Related articles





Knowledge bank

View all