2. 10W/40 oil has a thick viscosity, which is of four seasons type and is generally used in summer. The price of this oil is about 255 yuan, semi-synthetic engine oil, 4L package.
Mobil lubricating oil is an ultra-high viscosity synthetic lubricating oil with excellent performance, which is specially designed for heavy-duty and low-speed gears that are often in the state of boundary lubrication. These products are made of synthetic base oil. Although they have such a high viscosity grade, they still have unique low-temperature fluidity.
Extended data:
The engine is the heart of a car. There are many metal surfaces rubbing against each other in the engine. These parts have fast moving speed and poor environment, and the working temperature can reach 400℃ to 600℃.
The brand-new PurePlus technology can make natural gas into crystal pure synthetic base oil, and on this basis, add unique power cleaning technology to create lubricating oil with super clean and protective performance. Under such harsh working conditions, only qualified lubricating oil can reduce the wear of engine parts and prolong the service life.
Engine oil on the market can be divided into mineral oil and synthetic oil because of the difference of base oil (vegetable oil is not counted because of its scarce output). Synthetic oils are divided into: fully synthetic and semi-synthetic. Lubricating base oils are mainly divided into mineral base oils and synthetic base oils. Mineral base oil is widely used, with a large dosage (about 95% or more), but in some applications, products mixed with synthetic base oil must be used.
Requirements:
As a kind of machinery, engine has the same requirements for lubricating oil as general machinery, such as proper viscosity, certain performance requirements such as oxidation resistance, wear resistance, corrosion resistance and viscosity temperature. But the engine is a special kind of machinery, and its requirements for lubricating oil have its own special side, and its particularity mainly includes:
1) The general requirements for the engine are small volume, light weight, compact mechanism and high output power, so it bears a great load on the unit friction surface.
2) Besides the friction heat, it is also affected by the combustion heat, so the temperature of the friction surface is very high, which reduces the viscosity of the lubricating oil and is not easy to form an oil film.
3) The high-temperature and high-pressure combustion gas in the combustion chamber will leak into the crankcase through the gap between the piston, piston ring and cylinder liner. These combustion gases are gases and some particles (smoke and dust) produced by complete combustion and incomplete combustion of fuel oil and a small amount of lubricating oil, which usually become the main components of crankcase blowby, and will pollute lubricating oil and promote its oxidation under certain conditions.
4) Lubricating oil needed around the combustion chamber enters through the gap between the piston and the cylinder liner and the gap between the valve stem and the valve guide, so it is difficult to supply oil.
5) When working, the piston and the valve move back and forth, so the relative speed of the upper and lower dead points is zero, and it is difficult to form an oil film. Piston pin and bushing swing, and oil film is difficult to form.
References:
Mobil lube oil-Baidu encyclopedia