Why do cylinders now do not need oil lubrication, and what technology has changed the lubrication wi

All the parts of the car that can rotate and move must be lubricated, otherwise they will wear out quickly. Some are liquid lubricating oils that need to be replaced regularly, and some are lubricating greases that do not need to be replaced.

For example, the ball cage of the half-shaft and the ball head outside the tie rod of the steering machine are all lubricating grease, as long as the rubber sleeve wrapped in these greases is not damaged and the grease leaks, they do not need to be replaced for life.

Precautions: In the usual maintenance of buses and trucks, there are items that add grease to each moving part, and there are special adding openings, which can be directly driven into it with a grease gun. The car does not need to do this maintenance, and the wheel bearings are also lubricated with grease.

But it is a fully sealed monolithic structure. This bearing is closed, and the grease inside will not flow to the outside, and the dirt from the outside will not enter the inside.

1) "Vehicle" means motor vehicle and non-motor vehicle.

2) "Motor vehicle" refers to a wheeled vehicle that is driven or towed by a power unit and driven on the road for personnel or for transporting goods and carrying out special engineering operations.

3) "Non-motorized vehicle" refers to a vehicle driven by human or animal power on the road.

and motorized wheelchairs and electric bicycles for the disabled that are driven by power units but are designed to meet the relevant national standards in terms of maximum speed, empty mass and dimensions.

and other means of transportation.

Lubrication reduces friction, the cylinder can reduce friction and wear through machining accuracy, and the seal of the cylinder seal is improved to improve the wear resistance of the seal, and the seal uses dry friction lubricant, which can improve the auxiliary lubrication outside the cylinder.

The oil is thrown into the piston through the splashing effect of the crank rotation and the oil passage in the crankshaft, and then flows into the piston and the cylinder through the small hole for lubrication, and then the oil is scraped off by the oil ring and flows back into the engine, and so on repeatedly.

There is a rapid relative slip between the piston and the cylinder, between the spindle and the pad, and to prevent the parts from wearing out too quickly, an oil film needs to be created between the two sliding surfaces. An oil film of sufficient thickness separates the surface of the relatively sliding part to reduce wear.

The oil has a low specific calorific value and is not inherently coolant inside the engine. However, due to the heat generated by fuel combustion in the engine, when the engine is working, the oil can bring the heat back to the oil tank and then dissipate it into the air to help the water tank cool the engine, and the real cooling effect is the water (or antifreeze liquid) outside the engine case.

The piston ring blocks the oil and does not enter the cylinder, and the piston and cylinder head squeeze the gasoline before combustion.

There is a certain gap between the cylinder and the piston, in addition to the air ring, there is an oil ring, there is a small hole under the oil ring, the oil passes through the splashing effect when the crank rotates, and the oil passage in the crankshaft, the oil is thrown into the piston inside, and then flows into the piston and the cylinder through the small hole for lubrication, and then the oil is scraped off by the oil ring and flows back into the engine, so repeated lubrication, it is because of the sealing role played by the piston ring (including the air ring and the oil ring) that the oil will not run into the combustion chamber to burn, if the piston ring or cylinder block is worn, it will make the gap between them larger, the piston ring can not start a good sealing effect, and the oil can not be scraped, and the phenomenon of burning engine oil will appear.

In the case of a two-stroke engine, the oil is mixed with gasoline and burned and lubricated, and after lubrication, it is discharged with the exhaust, and the blue smoke from the muffler is.

It is mainly operated by piston rings.

Scrape the oil off by the oil ring, and you will definitely have to burn it somewhat.