First, the ship's oil is usually high in oil.
Due to the high sulphur content of Marine fuel, (a variation within 0.5% ~ 3.5% range), the lubricating oil must have sufficient alkali retention to neutralize the acid generated by the combustion of fuel.

Second, the ship's oil resistance is good.

It is inevitable that the ship will encounter water pollution at sea. Therefore, it is required that the Marine lubricating oil must have good anti-emulsifying performance and water separation performance, while the diesel oil of the land use diesel engine has no such working condition and no such requirement.

In addition, ship oil has all the other properties of diesel engine oil.

Marine fuel main classification.

It is mainly divided into: light oil and heavy oil.

The light oil is Marine diesel, which is used by MGO and MDO, etc., for use in motor navigation, such as entering and leaving port, entering and leaving the narrow channel, and strong wind and wave weather;
Fuel oil (heavy residue) is often said that the 180 and 380 CST, normally used for sea voyage. So this type of shipping the entire fuel system is divided into totally independent system, diesel fuel oil with high viscosity and system. Also some oceangoing ships only with heavy fuel oil as raw material, do not use diesel, this type of ship in refueling, must consider the effect of sulfur content restrictions, especially when the port of destination in the European Union (environmental factors).

Marine light diesel oil, mainly for high-speed diesel and medium speed diesel engine used, mainly for short distance navigation power of middle and small boats, such as the Yangtze river and canal navigation canal sand boat, fishing boat, dry bulk carrier, or for Marine auxiliary power;
Also used is a type 4 ship oil, which is composed of heavy diesel oil and fuel oil, which is intermediate in fuel oil and diesel, and is suitable for medium-speed diesel engines.