Expert Q&A: Powering Next-generation Gas Engines
Shell’s Luis Garcia explains how Shell Mysella S7 N Ultra extends oil drain intervals, helping to ensure greater reliability,reduce downtime, protect components and lower total cost of ownership.
Luis Garcia, Technology Manager, Marine and Power Engine Lubricants, Shell
Why was Shell Mysella S7 N Ultra developed?
The rising global demand for power is driving the ongoing evolution of stationary gas engines. However the more powerful the engine, the more extreme the operating conditions of the lubricating oil. An oil that can withstand higher stress to help ensure engine reliability and enhance performance is key.
Following extensive scientific research and more than 45,000 hours of testing to date on the latest 4-stroke, spark-ignition steel piston engines, the result was Shell Mysella S7 N Ultra. It is approved by INNIO for Jenbacher gas engines Type 6 versions C, E, F, J, H, K, Type 2 and Type 3 for fuel gas Class A (natural gas).
A product borne out of close OEM collaboration to better understand and tackle the challenges of modern operating environments. Leveraging all accumulated engineering, design and lubrication experience to select the right base oils and advanced additive technology.
How is Shell Mysella S7 N Ultra different to previous products?
What sets Shell Mysella S7 N Ultra apart from other products on the market is the technology platform on which it has been developed. With this new product innovation, we have worked to meet the needs of forward-looking engine manufacturers, and are committed to helping gas plant owners to better future-proof their business, so they can keep up with the growing demand from the industry.
Shell Mysella S7 N Ultra performs significantly above current industry standards and against other products in this space. Consider that the typical oil drain interval for steel piston engines is around the 2,000-hour mark with top tier oils. With Shell Mysella S7 N Ultra, we are able to demonstrate drain intervals of up to double that length. *Results are supported by 45,000+ hours of field trials in more than 10 Jenbacher Type 6 engines.
For what kind of operating environments is Shell Mysella S7 N Ultra designed?
Typical break mean effective pressure (BMEP) in previous generation stationary gas engines for power generation reached up to 22 bar in the power cylinder. As the latest steel piston engines operate at 24 bar BMEP, we have designed Shell Mysella S7 N Ultra to cope with these significantly higher pressures and deliver extended oil drains. It also has the capacity to support engines developed in the future with an even higher BMEP.
Just as engine manufacturers are continuously improving the efficiency of their engines, we are pushing the boundaries to create the next generation of oil. Working in collaboration to help them achieve their operational goals.
Is Shell Mysella S7 N Ultra fully compatible with other products?
Shell Mysella S7 N Ultra engine oil is fully compatible with other products on the market. However, to unlock its full benefits, we would recommend that operators completely drain the engine lubricating system before application to avoid combining with the previous oil, which could compromise its performance.
Why is Shell Mysella S7 N Ultra particularly suited for the most stressful engines?
The greater the efficiency of the latest stationary gas engines, the higher their operating pressures and temperatures. Sensitivity to knocking, and other potential combustion chamber issues in these engine designs, have been managed through lower lubricant consumption rates. As a result, oil stress levels are significantly higher in the most efficient engine designs. Shell Mysella S7 N Ultra has been specifically designed to handle higher stress levels in the harshest operational conditions.
It will keep the engine running reliably, even with increased residence time of the oil on the hot engine parts at lower oil consumption levels; a growing trend amongst the latest stationary gas engines. Other lubricants with a poorer oil life or deposit control would not be able to perform as well.
The product’s ash level benefits a lower oil consumption environment, since it effectively works to lubricate valve seats on the cylinder head, preventing valve recession. This is not necessarily the case for the previous generation of low ash engine oils.
What is the oil’s impact on total cost of ownership?
As our field tests demonstrated, Shell Mysella S7 N Ultra has an ultra-extended oil life; up to double that of previous generation premium gas engine oils. This is achieved through improved oxidation resistance, base number retention and optimum viscometrics. It also offers excellent control of deposits, as well as improved overall engine protection through advanced formulation technology. *Results are supported by 45,000+ hours of field trials in more than 10 Jenbacher Type 6 engines.
Ultra-extended oil drain intervals, engine protection and system efficiency decrease the frequency of engine inspection, the need for repair and the purchase of replacement parts. Helping to reduce time spent on maintenance and total cost of ownership, and increase operational reliability.
How does Shell Mysella S7 N Ultra benefit day-to-day running of an engine?
Keeping piston assemblies clean can effectively prevent scuffing, which can be caused by deposits accumulating in the ring grooves, impacting how piston rings move. Excessive deposits can result in either lack of movement or abnormal movement, such as rings being pushed unevenly towards the cylinder liner. This can result in scuffing and lead to a power unit failure, forcing the engine to be stopped for corrective/unplanned maintenance with consequences for operational efficiency.
Shell Mysella S7 N Ultra delivers excellent deposit control and handling for trouble-free piston running, which helps boost engine efficiency, avoid unplanned downtime and means predictive maintenance intervals can be followed as determined by the manufacturer. *Results are supported by 45,000+ hours of field trials in more than 10 Jenbacher Type 6 engines.
How can choosing the right lubricant result in long-term benefits for gas engine owners and operators?
There are many long-term benefits of choosing the highest performing lubricant, all of which help keep energy companies running and ultimately boost the bottom line. In summary:
Maximum productivity: extending oil drain intervals, especially if they are synchronised with predictive maintenance, means reduced downtime and equipment is working harder for longer.
Increased reliability: ensuring the smooth running of the engine means you avoid unplanned maintenance. This is almost impossible to quantify, highly disruptive and could even lead to the loss of business.
Reduced total cost of ownership: lowering the frequency of expensive engine part replacement, thanks to excellent deposit handling and wear prevention, will save you money.
Better planning: determining maintenance intervals or oil drains means you can more easily plan your operations from a business perspective.
How can a product such as Shell Mysella S7 N Ultra benefit maintenance practices?
An excessive accumulation of deposits on a piston assembly not only increases maintenance needs, but may result in the need to replace entire components, including the power unit itself.
Meanwhile a cleaner piston ring assembly on a power unit means that the time required to undertake planned maintenance can be greatly reduced.
Using the high-performance Shell Mysella S7 N Ultra can improve the condition, and maximise the potential of, engine parts, until the next planned maintenance. This means customers can reap the benefits of component-designed lifetimes, planned costs and scheduled downtime. In some cases there is the potential to extend part lifetime and therefore enjoy additional cost savings.
How can a product such as Shell Mysella S7 N Ultra benefit health and safety?
The less a maintenance team needs to manipulate large engine parts, or actually dismantle and reassemble the full engine, then the less exposure to risk.
Customers’ health and safety are a priority for Shell. As with all our lubricants, Shell Mysella S7 N Ultra has been developed with consideration for HSSE requirements. Reducing the risk from the molecules involved in our technology, and developing lubricants that are as HSSE-friendly as possible, are key ambitions for Shell’s ongoing product innovation strategy.