All the major lubricant manufacturers have now ensured the 40 BN formulations are compliant with MAN Energy Solution’s Cat II requirements for cylinder oil detergency.
MAN’s May 2020 Service Letter SL2020-694 defined a new category of higher performance cylinder oils (Cat II) for MAN B&W Mark 9 engines and subsequent generations that set a special focus on piston cleaning ability. MAN indicated that improvements in engine design meant that their highly fuel-efficient engines operating with higher pressures and higher temperatures required lubricants with matching performance.
All of the major lube oil suppliers now offer approved MAN ES Category II 40BN solutions.
Cat II cylinder oils are applicable for all engines (e.g. Mark 8 and lower) and recommended for MAN B&W two-stroke engines Mark 9 and higher. Cat II status automatically gives a Cat I status.
The first cylinder oils to go through the Cat II process were 100 BN and 140 BN oils, with 40 BN oils now following and largely available globally. The result is 40 BN products that have the cleaning performance of a 100 BN, so that it is no longer necessary for engines operating on very low sulphur fuel oil (VLSFO) to switch between the two. MAN recommended the practice before the introduction of the new Cat II standard.
Castrol’s new cylinder oil, Cyltech 40 XDC (eXtra Deposit Control), has successfully attained a Category II No Objection Letter (NOL) from MAN. The Cyltech range has been formulated to protect liners in engines operating under corrosive conditions by keeping liners, pistons and piston rings clean while reducing wear. The range includes options tailored to reduce deposits and prevent hard ash build-up for a variety of steaming conditions and specific fuel sulphur levels. Testing on Castrol Cyltech 40 XDC included over 2,000 hours running on a MAN BW 7G80ME-C9.2-TII engine burning < 0.5% sulphur VLSFO.
Shell Marine has received an NOL for Shell Alexia 40 XC, a 40BN cylinder oil. Shell Marine notes that the new Alexia 40 XC lube oil uses a proprietary and unique formulation, developed by Shell Marine’s in-house Research & Development team.
Dr Luis Garcia, Technology Manager for Marine and Engine Lubricants, Shell Marine, said: “With the industry focused on reducing emissions, engine technology is continuously evolving to deliver higher efficiencies when operating with very low to zero sulphur fuels. Latest engine designs operate with challenging conditions in terms of pressure and temperature, demanding for higher performing lubrication, particularly in terms of engine cleanliness, making the development of a Cat II 40 BN cylinder oil essential.”
Gulf Oil Marine’s NOL for its Cat II 40 BN cylinder oil, GulfSea Cylcare XP 5040X, was extended by three years in May 2022. The extension follows from the successful completion of more than 2,000 hours of confirmation tests. The performance of the oil has been affirmed on two different engine models – MAN Mark 9.2 and Mark 9.5 – both running on low-sulphur fuels.
GulfSea Cylcare XP 5040X has an innovative dispersant technology that’s combined with non-alkaline detergents, anti-oxidant and wear-protection chemistries. Gulf Oil Marine says these technologies underpin its superior deposit-control performance, leading to significant cleanliness and wear-rate improvements versus regular BN40 products (circa 40% improvement, based on data collected on customer vessels in real time operating conditions) and hence helping to extend engine component life.
ExxonMobil’s 40 BN Mobilgard™ 540 AC has attained an NOL. ExxonMobil says its balanced formulation methodology ensures that Mobilgard 540 AC helps vessel operators wishing to simplify lubricant management through use of a single, low BN Category II cylinder oil. Operators can gain further confidence in the level of their engine’s reliability through implementation of an onboard scrape down oil analysis programme, such as MobilServ Cylinder Condition Monitoring.
Infineum’s M7095, an approved 20 BN marine diesel cylinder oil additive package, can now be combined with Infineum’s performance booster additive package to meet 40 BN requirements. The combination has a comparable piston cleanliness of a 100BN Cat II cylinder oil at the same feed rate. This helps optimization of lubricant consumption while lowering emissions.
Infineum’s testing involved 3,200 running hours on a vessel operating on VLSFO fitted with a 6G60ME-C9.5 engine, and a field test of 1,500 running hours on a vessel running on distillate fuel fitted with a 6S35ME-B9.5 engine.
Lubmarine has gained a NOL for its Talusia HD 40 lubricant. Serge Dal Farra, Lubmarine Marketing Manager, reminds: “All OEM guidelines recommend careful engine monitoring and a sophisticated intelligence-led approach allowing for the most prudent management of two stroke marine engines.”
