Patent ID: 9464254
Filing Date: 2016-10-11
CPC Classification: C10M,C10N

Claim Text:
1. A method of operating a two-stroke, cross-head slow-speed compression-ignited engine comprising (i) fuelling the engine with a diesel fuel, as a pilot fuel, and with a low sulphur fuel, as a main fuel; and (ii) lubricating the cylinder(s) of the engine with a cylinder lubricant having a base number (BN) of 20 or less and having a detergent additive system comprising at least two different metal detergents each having one surfactant selected from phenate, salicylate and sulphonate, wherein at least one of the metal detergents in the detergent additive system includes phenate as the surfactant, and has a total base number (TBN) as determined by ASTM D 2896-98 of greater than 200 mg KOH/g, and at least one of the metal detergents in the detergent additive system includes sulphonate as the surfactant, and has a total base number (TBN) as determined by ASTM D 2896-98 of greater than 100 mg KOH/g; or one or more complex metal detergents containing two or more different surfactants selected from phenate, salicylate and sulphonate, wherein a least one of said complex metal detergents comprises a complex metal phenate/sulphonate detergent or a complex metal phenate/sulphonate/salicylate detergent, and has a total base number (TBN) as determined by ASTM D 2896-98 of greater than 200 mg KOH/g.