Paul Harrold News

Castrol Marine said it has welcomed new guidance from Wärtsilä that undermines claims that mid-range base number (BN) oils represent a single cylinder oil solution for marine two-stroke engines. The advice confirms Castrol’s long-held concerns that using mid-range BN cylinder oils with higher sulphur fuels when slow steaming could lead to cold corrosion. The engine major has withdrawn approval for mid-range (50-60BN) cylinder oils when used with many marine engines running on Heavy Fuel Oil of above 2.5% sulphur content. New ‘letters of no objection’ to suppliers limit use of mid-range BN oils on all “Wärtsilä RTA, RT-fl ex and W-X engines as well as Sulzer two-stroke engines” to HFO whose sulphur content is “in the range 0.5<S<2.5 mass %”.

”We have responded to increasing demand from our customers for wider availability of our Cyltech 80 AW cylinder oil by expanding the supply network from five to 35 ports in key regions,” said David Goosey, Castrol Marine’s Chief Executive and Sales Director. Ports where customers will be able to book supplies will now take in major trading centers, including Antwerp, Rotterdam, Le Havre, Marseille, Hamburg, Bremen, Kiel, Singapore, Port Klang, Busan, Ulsan, Los Angeles, San Diego, San Francisco, Fujairah, Dubai, Jebel Ali and Khor Fakkan. Castrol’s recommendation that owners adopt Cyltech 80 AW was initially prompted to address the implementation of slow steaming practices by operators of large containerships fitted with large bore 2-stroke crosshead main engines.

Concerns over corrosive wear risk in cross-head engines led Castrol Marine to question the rigour of some widely used scavenge drain oil analysis (SDA ) techniques. Factors influencing scavenge drain oil characteristics include fuel sulphur level, cylinder oil BN level, system oil contamination and operating profile. Accuracy is critical in SDA interpretation, not least because it supports feed-rate assumptions that are critical to cylinder oil performance, Castrol said. “It is not possible to analyze results accurately without comprehensive knowledge of the fuel oil, the new and used system oil, feed rates and operational data collected from the engine at the time of sampling,” said Paul Harrold, Castrol Marine Technology Manager.

MAN Diesel & Turbo supports Castrol’s advice that misapplication of mid-range base number (BN) cylinder oils can cause corrosion. Castrol inform that the engine manufacturer recently issued service letters that recommend “cylinder lube oil with 70BN or higher” for latest generation super long stroke engines using higher sulphur fuel (above 1.5%-2%). MAN says it “cannot recommend” cylinder oils “with a BN level between 50 and 60” for these engines. Ship-owners have been persuaded to try a host of new mid-range lubricants on the basis that they offer a solution across the range of sulphur content in fuel oil, including during slow steaming operations.

Castrol Marine has extended its cylinder oil range to address concerns about engine damage and performance as slow steaming and fuel sulphur content restrictions bite. The specialized marine lubricant supplier has launched Cyltech 80 AW, an 80 BN (base number) cylinder oil. The Cyltech range has been developed for optimum engine protection in 2-stroke crosshead engines and specifically to match engine performance with the demands of varying sulphur fuels and the impact of slow steaming.

Drawing on OEM reports and its own engine performance tests, Castrol Marine has strengthened its conviction that optimum performance, when slow steaming, can only be achieved by having a range of cylinder oils available for the customer. content and low feed-rates. to those vessels regularly slow steaming, to ensure piston ring packs and liners remain in excellent condition. “The idea of a single, mid range cylinder oil solution for all vessels as sulphur limits are reduced may be seductive…