Cylinder structure of engine cylinder group

Due to the action of high temperature and high pressure gas and the contact with the piston moving at high speed, the inner surface of the cylinder is easy to wear.

In order to improve the wear resistance and service life of the cylinder, there are different cylinder structures and surface treatment methods.

There are three types of cylinder structures.

That is, no cylinder liner, dry cylinder liner and wet cylinder liner.

Dry cylinder liner engine block

It means that the dry cylinder liner is press-fitted or installed in the cylinder liner seat hole of general gray cast iron body and does not contact with the coolant. The outer surface of the dry cylinder liner and the inner surface of the cylinder liner seat hole must be finely machined to ensure the necessary shape and position accuracy and facilitate disassembly.

Wet cylinder liner

The outer wall of the cylinder liner is in direct contact with the coolant. The wall thickness of wet cylinder liner made of alloy cast iron is generally 5 ~ 8 mm, and the lower part of wet cylinder liner is sealed with 1 ~ 3 heat-resistant and oil-resistant rubber sealing ring to prevent coolant leakage. The upper seal of the wet cylinder liner is that the top surface of the cylinder liner is 0.05~0. 15mm higher than the top surface of the cylinder liner after the cylinder liner is installed in the engine block.

Air-cooled engine cylinder structure

Because the heat transfer coefficient of metal to air is only 1/33 of metal to water. Therefore, it is necessary to cast fins on the outer wall of the air-cooled cylinder to increase the heat dissipation area and enhance the heat dissipation ability.