Varying approaches to the cylinder lubricant dilemma

Some producers, such as French company Total Lubmarine, believe they can cover all normal requirements with a single, universal, oil, while others, such as Castrol Marine, feel that different grades are necessary for use with high and low sulphur heavy fuels and distillates.

Total Lubmarine reports a good take-up for its one-size-fits-all solution, Talusia Universal, with rising sales – in fact a 22% increase over the last 12 months compared with the corresponding previous period. The oil was first launched in 2008since when, according to Total, over 3,000 vessels have adopted it, representing more than 70% of Lubmarine's customers. The company claims that Talusia Universal has successfully clocked millions of hours across multiple routes and a range of engine types.

According to Lubmarine, Talusia Universal is the only such cylinder oil in the market that can provide a one-step solution for managing ECA transitions as well as the demands of slow steaming. In fact Total believes that the oil’s suitability for slow steaming is the main driving force behind the increase in demand, said to average out at over 100 vessels per month switching to the universal lubricant since December 2010. Additionally, a significant growth in Asian sales is partly attributed to ship owners and operators trading across ECAs and recognising the lubrication challenges posed by switching between high and low sulphur fuel.

Total says that Talusia Universal is compatible with fuel of sulphur levels from 0.5% up to 4.5%, meaning that the requirement to switch lubricants to match different fuel sulphur levels is removed. This, says the company, simplifies onboard operation as only one cylinder oil has to be managed. This is in turn is said to improve safety because there is no risk of mismatching the cylinder oil while changing bunker fuels with a different sulphur content.

Lubmarine’s technical director, Jean-Philippe Roman, explains that Talusia Universal effectively meets the challenges facing ship owners and operators now and over the coming years. Talusia Universal’s characteristics are said to ensure:

• better handling and control of the deposits resulting from contaminations and varying operating conditions;
• better control of lubricant degradation to avoid detrimental lack of performance during its lifetime on the liner surface;
• significantly higher resistance to wear to insure the reliability of the high rated engines; and
• flexible basicity with high neutralisation efficiency to cover operations with the whole range of fuels available.

Roman says: “To meet the demands of tomorrow, the chemistry of marine cylinder lubricants must change today. The right choice of lubricants has become increasingly significant to ensuring both efficient vessel operation and environmental regulatory compliance. We know that ship owners and operators are under tremendous pressure to deliver against current and impending SOx and NOx regulations, reduce bunker fuel costs through slow steaming and meet safety standards to protect both their workforce and the environment. All of which can place conflicting demands on marine engines.”

The latest Talusia Universal development is based on ash-free neutralising molecules (ANM). The Talusia Universal ANM product will, says Total, manage the evolving demands associated with future use of HFO and distillates. The new chemistry will provide improved detergency and thermal stability; extended deposit control due to a lower calcium content; high neutralisation efficiency and increased anti-wear ability.

Roman concludes: “Amid an ever-changing regulatory landscape, we understand that our customers need to maintain a clear competitive advantage through reliable, consistent operations as they strive for profitability in continuing turbulent times. The success of Talusia Universal and development of new patented chemistry for marine cylinder lubricants is testament to Lubmarine’s commitment to delivering tomorrow’s lubricants today.”

Castrol takes a different approach. The company believes that adoption of increasingly severe slow steaming regimes, primarily to save expensive bunker costs but also to keep ships working instead of laid-up, is becoming standard practice across a widening range of sectors. According to Castrol, offering a full range of OEM-approved cylinder oils is the only way to ensure that shipowners’ performance demands can be fully met in today’s demanding operational environment.

Castrol says that until quite recently, many shipping companies concentrated on trying to find the most efficient cylinder oil feed-rate taking into account the sulphur content of the heavy fuel oil in use. With the development of slow steaming practices a further variable now has to be considered, making it a more complex equation to calculate which cylinder lubricants offer the most efficient cylinder lubrication solution. The company’s research has produced evidence to show that, while slow steaming, when engines are operated significantly below original design loads, the liner temperatures are significantly reduced, which increases the problem of corrosion on piston rings and cylinder liners. This is particularly true when using higher sulphur fuels if a cylinder lubricant of insufficient base number (BN) is used.

Castrol is taking what it says is a ‘distinct position’, in pointing out that current and emerging fuels and operating conditions require a comprehensive set of cylinder oils. It says that it is regularly being asked by shipping companies for help in making the right choice; and the company claims a wide range of OEM approvals and a number of technical experts available to assist customers in their decisions.

Although Castrol agrees that in ideal conditions shipping companies would prefer to only have to use one cylinder oil that would work with a variety of different sulphur fuels, engine inspections carried out recently suggest that such a desire for simplicity may be compromising reliability, particularly under slow steaming conditions.

Castrol believes that the balance between fuel sulphur levels, cylinder oil feed rates and cylinder lubricant BN becomes more complex under slow steaming conditions and requires a range of cylinder lubricants to provide an optimum, cost effective lubricant solution. The company says that what was a two-dimensional difficulty has evolved into a three-dimensional problem.

“We have field evidence that slow steaming is leading to corrosive wear when lower BN lubricants are used with relatively high sulphur fuels,” says Paul Harrold, technology manager marine & energy lubricants. He says that Castrol offers a range of OEM -approved cylinder oils, with possibly the widest customer base. Harrold cites, as further support for this view, a recent service letter from a leading engine maker advising that, when ships are slow steaming, operators should increase feed rates due to incidences of corrosive wear.

Harrold also points out: “If customers follow OEM feed-rate guidelines for slow steaming operation, the consequence of using 60 BN instead of 70 BN leads to an increase in annual cylinder oil consumption. We estimate that the increased consumption could be in the order of 5-10%, depending upon engine type and manufacture when using typical fuels.”

“We believe that the current challenge of slow steaming combined with impending fuels legislation means that optimal cylinder lubrication for vessels can only be achieved under all load conditions by a range of cylinder lubricants,” Harrold says. “Operators that adopt a single cylinder lubricant strategy should be mindful of the compromises they are making and risks from adopting such an approach need to be fully understood and properly managed.”