Cylinder Oil Blending Unit - COBU


Cylinder oil is essential for the two-stroke engine. Today’s cylinder oils are made with a complex chemistry, and the individual feed rate must therefore be assessed for each oil brand, viscosity class and BN level.

The cylinder oil is used to achieve the necessary level of detergency and dispersion to keep the piston rings and crown clean, and the necessary base number (BN) to neutralize the acids formed during combustion to prevent cold corrosion. The main acid to be neutralized is the Sulphur acid produced from the Sulphur content of the fuel burnt in the engine.


With varying Sulphur content and grade of fuel oil, two stroke engines need right BN cylinder oil. Lubricant suppliers are finding it practically difficult to supply required different BN oil, and vessel too cannot set up numerous cylinder oil storage tanks for different grades.

In order to match the properties of the commercially available cylinder oil with the Sulphur content, VTS and Gulf Oil Marine have recently developed a Cylinder Oil Blending Unit (COBU).

COBU is a unit able to blend two different lubricating oils at different BN to obtain a custom BN. The unit is fully automatic allowing the oil blending to obtain the required BN, the oil heating and the precisely measure of the oil consumption. The unit can be easily mounted onboard replacing the heater tank.


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