There are two kinds of crankcase oil for diesel engine, which are crosshead and cylindrical piston.The crankcase is separated from the cylinder in the crosshead diesel engine, so the working condition of crankcase oil is relatively mild.The normal consumption rate is about 0.1-0.3g /(kW·h).It is mainly used to lubricate the bearings and guide plate etc. In some diesel engines, it is also used to cool down the piston or as the operating mechanism hydraulic control oil.The requirements for this oil are as follows:
(1) the crankcase oil must have appropriate viscosity to guarantee the oil film establishment.Because the Marine diesel engine often works under variable working conditions and the ambient temperature changes greatly, it is required to work reliably in a wide range of temperature, that is, it has better viscosity-temperature characteristics.Should be adopted according to the experience of using, the oil viscosity at 100 ℃ for 11 was 14 was/s/s ~ (the equivalent of SAE30), viscosity index is about 80-80.
(2) anti-corrosion performance and anti-corrosion performance are of great significance to the bearing shell, which may lead to corrosion of bearing alloy or peeling of coating layers such as lead tin and lead indium.Crankcase oil must be added with anti-oxidation and anti-corrosion additives.
(3) cleaning and dispersing oil can disperse small particles such as carbon particles or clay particles and suspend them in the oil so as to filter them out.
(4) anti-oxidative stability crankcase oil should have anti-oxidation performance (cooling piston) at a higher temperature. The crankcase oil used for bearing lubrication is prone to oxidative deterioration when in contact with air, which requires good anti-oxidative stability.Normally, should control the oil temperature not over 82 ℃, to control the oxidation rate.
(5) others such as anti-emulsification performance, anti-foam performance, flash point, etc.
The crankcase oil of cylindrical piston diesel engine is not only used to lubricate the bearings in the crankcase, but also to be used as cylinder lubricating oil.The normal consumption rate is about 1.07 ~ 1.6g/(kW·h).In addition to all the requirements for crankhead crankcase oil, it should meet the following requirements.
(1) cleanliness in high-temperature operation.At high temperature, it can ensure that all kinds of sediment do not adhere to the parts and should be suspended in oil.
(2) good thermal oxidation stability.
(3) enough alkalinity.It is required to neutralize sulfuric acid produced by combustion of inferior fuel.Generally, TBN = 22mgKOH/g ~ 34mgKOH/g.
(4) high viscosity requirement.The lubricating oil equivalent to SAE20, SAE30 and SAE40 should be available according to different service conditions.
To sum up, crosshead diesel engine and cylindrical piston diesel engine and crankcase oil require different quality grades due to different working conditions.
Zhenjiang haishun Marine equipment co., LTD. Is a professional production and sales of Marine diesel engine parts at home and abroad operating companies, the company has been applied for the university of technology internal combustion engine research institute professor Chen daochun as a technical director and consultant, quality for survival, reputation for development.
Our company mainly supplies large vessels in China: zhonghai group, cosco group, east China sea rescue bureau of the ministry of communications, south China sea rescue bureau, north sea rescue and fishing bureau, Marine bureau, etc., and Yangtze river shipping system units, providing high-quality and convenient Marine diesel engine, Marine diesel engine parts, diesel engine parts.