Cylinder Maintenance Skills and Common Failure Modes

First, let's understand what a diesel generator cylinder is. The cylinder is where the air - fuel mixture burns and performs work. Inside the diesel engine cylinder, the clean air filtered by the air filter is fully mixed with the high - pressure atomized diesel sprayed from the fuel injector. Under the compression of the upward - moving piston, the volume decreases, the temperature rises rapidly, and reaches the ignition point of diesel. The diesel is ignited, the mixture burns violently, the volume expands rapidly, and pushes the piston downward, which is called "doing work".

The working environment of the cylinders in a diesel generator set is extremely harsh. Specifically, it has the following characteristics:

1.The inner surface is directly exposed to the action of high - temperature and high - pressure combustion gases.

2.There are drastic temperature changes during the working process. During the combustion process, the temperature of the combustion gas can reach about 2000°C, while the temperature of the cold air during the intake process is only a few dozen degrees Celsius.

3.The outer wall of the cylinder is affected by the cooling water, which causes severe corrosion.

4.The reciprocating motion of the piston generates alternating stress, resulting in severe wear of the cylinder.

Since the cylinder operates under the above - mentioned harsh conditions, it can be said that the cylinder is truly in a "severe environment" during operation. The degree of cylinder wear is the main basis for major overhauls of diesel engines and determines the service life of diesel engines. Therefore, it is very important to try to reduce cylinder wear.

Dingbo Power, a diesel generator manufacturer in Guilin, shares the common failure forms of cylinders:

1.Deposition of scale on the outer wall of the cylinder liner: The main components of scale are insoluble substances such as CaCO3, MgCO3, CaSO4, and MgSO4.

(1) Main cause of scale formation: The cooling water contains minerals, which are deposited under the action of high temperature and firmly adhere to the outer surface of the cylinder liner.

(2) Harm of scale deposition on the outer wall of the cylinder liner: The volume of the water jacket decreases, the circulation resistance increases, and the cooling effect declines. It has been measured that the heat - transfer coefficient of scale is only 1/25 of that of steel.

(3) Treatment of scale: During the overhaul of the diesel engine, the scale adhering to the outer wall of the cylinder liner should be carefully cleaned. To reduce its impact, the diesel engine should use cooling water with less minerals or soften hard water, and try not to use hard water (water with a high mineral content).

2.Cavitation of wet cylinder liners: The so - called cavitation of wet cylinder liners refers to the honeycomb - like clusters of holes that appear on both sides of the outer surface of the cylinder liner along the swing direction of the connecting rod after the diesel engine has been in use for a period of time (in severe cases, often after running at high load for dozens of hours).

Cause of cavitation in diesel generator sets: There are microscopic pores, cracks, and grooves in the cylinder liner material, and the cylinder liner vibrates during the operation of the machine.

(1)Scuffing: Scuffing refers to the grooves of different depths that appear on the inner wall of the cylinder liner along the moving direction of the piston.

(2)Cracks

(3)Wear

Dingbo Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to [email protected] we will pay highly attention on your question.