30AUG2019 - NEWS - New cylinder lube oils: more than just BN index

The 2020 sulphur cap will impact a range of technologies and engineering practices, key among them being lubrication, especially cylinder lube oils. The cylinder lube oil’s essential function is to lubricate and help seal the combustion chamber by sealing the interface between the piston ring and the liner. Other functions include protecting surfaces against corrosion and cleaning the combustion chamber and components.

To date, the high sulphur content of most bunkers coming in has led to a focus on the corrosion-fighting capability of cylinder lube oils. Cylinder lube oils have been identified through their base number (BN), which indicates acid neutralisation potential. In general, cylinder lube oils with lower BN will be appropriate for low-sulphur fuels; too high alkalinity in the cylinder lube oil will increase deposit formation.