During Riviera’s Optimum lubrication, optimum auxiliary machinery performance webinar, industry stakeholders shared their experience of vessel lubrication systems, offering advice on how to improve the lifecycle of lubricants and with it, the health of onboard machinery
Lubricants constitute a sizeable component of any vessel’s budget, yet most vessels in service are not optimally lubricated, an issue which accelerates machinery wear and increases drydocking costs. Discussing these issues during Riviera’s Optimum lubrication, optimum auxiliary machinery performance webinar, held on 24 November as part of the Marine Lubricants Webinar week, panellists C C Jensen global segment manager - marine/offshore Kim Kjær; Panolin Greenmarine Lubricants business development manager Phil Cumberlidge; and Shell Marine senior lubricant technical advisor Dirk Hoek considered how to get the best out of the various lubricants on the market.
Mr Cumberlidge began by looking at base oils, additives and the potential failures that can affect value and performance. Mr Cumberlidge said good lubricants are a marriage of good ingredients. “You need to look at how additives are added,” he said. “Are they individually selected?” he asked.
Turning to common failures, he flagged up the damage caused by high temperatures and oxidation “which causes varnish deposits. This is like the cholesterol in your body; it narrows the pipework and causes increased temperature due to reduced flow rate.”
He noted that in cold conditions, some base oils can exhibit additive separation, clumping together such that filtration can actually end up removing the additives that have been introduced to prevent harm.
Where water ingress can occur, he explained that a hydrolytically stable lubricant was required to ensure the oil is resistant to, or minimally affected by, water. “For hydrolysis,” he said, “which breaks down the oil and can increase acidity, you need a lubricant that can readily separate to have the water managed and taken out.” For gears and thrusters, he stated that a shear-stable lubricant was required to ensure the oil is resistant to the shearing effect of the gear teeth.
During the webinar, the audience was polled on the question: Have you used EALs?
63% said they had done so
Mr Cumberlidge said owners and operators should concentrate on identifying products that have optimised combinations of additives with the base oil. “Your vessel lubricants are assets; please select them wisely and look after them,” he said.
Mr Hoek moved the discussion on to the pertinent subject of monitoring, emphasising that a fleet’s annual lubricant consumption should be dependent on the performance of the lubricant. “Beyond the cost of overconsumption, the impact of maintenance costs can be huge if equipment is not lubricated well or where that lubrication process is uncontrolled and not effectively monitoring.”
Mr Hoek then listed various systems, explaining how best to monitor their operation. “For hydraulic systems,” he said, “the most important characteristics to watch during oil condition monitoring are viscosity, water content and contaminants. For gearboxes, it is very important to monitor and to select the right grade. High-speed engines,” Mr Hoek continued, “which in marine applications are automotive derivatives, are designed for standard automotive diesel, but you must monitor the sulphur content. For example, the automotive standard is approximately 15 ppm, but in marine it is 1,000 ppm. So there is a huge difference.”
During the webinar, the audience was polled on the question: Have you set your own oil cleanliness targets based on smallest dynamic tolerance?
54% said no to this question
He explained effective monitoring not only prevents damage occurring, but also helps extend the life of a lubricant, reducing costs. “Monitoring is really important to confirm you have the right lubricant in use, the optimum consumption rate is applied or the right oil drain interval, and the expected maintenance intervals or service life of the components can be reached.”
“The oil is actually the lifeblood in the new machine,” said Mr Kjær, who focused his presentation on the value of clean oil and critically, what constitutes ‘clean’.
“A rule of thumb says 80% of all oil-related system breakdowns is due to contaminated oil,” he said. “That’s a significant number and I have seen many cases where just clean oil could have kept the vessel out of drydock."
Mr Kjær emphasised the importance of considering all potential contaminants, be that particles, water, varnish, or bacteria. To keep machinery free of these pollutants, Mr Kjær discussed offline filtration, where the filter has its own pump. But he explained that without understanding the nature of all contaminants, even the best system would not be enough. “The most dangerous particle is the particle that fits in the dynamic tolerance, and the smallest dynamic tolerance you have is the old film thickness,” he said. “So it’s very important you are able to identify the smallest dynamic challenge because that is the particle size that you need to filter out.”
Mr Kjær said owners and operators should remember that an investment in filtration is actually an investment in clean oil. “When you talk to your suppliers, demand to know the level of cleanliness that will be achieved,” he said, adding “Focus on clean oil and ask your supplier to supply that, instead of just a filter.”
During the webinar, the audience was polled on the question: What is the most expensive impact for you – if you experience excessive water content in your thruster?
12%: loss of position
7%: oil change
44%: drydocking out of schedule
32%: wear and tear on components
5%: nothing, I just call for tug assistance