Third, the diesel generators fixed parts - cylinder liner

In order to save high-quality materials, reduce manufacturing costs, almost all diesel engines are used in the body inlaid cylinder liner structure popularity. Cylinder liner must have sufficient strength and stiffness, good wear resistance and corrosion resistance, proper cooling, lubrication and reliable seal.

Cylinder liner structure.

Water-cooled engine cylinder liner has the following two:

① wet wet cylinder in direct contact with the cylinder wall directly to the cooling water, as 2.18 (b) in Fig. Its characteristics are a good cooling effect, easy to manufacture, but the outer wall of the cylinder liner cooling water corrosion is more serious, and have reliable sealing measures.

② Dry Dry Liner cylinder wall is not in contact with the cooling water, cooling water is flowing in the closed space of the cylinder block, as shown in 2. 18 (a) above. This liner is poor due to the cooling effect, processing requirements, disassembly repair inconvenience, it is seldom used.

2 wear. Cylinder liner

Since the cylinder liner wear reasons, therefore, the measurement, lower, left and right is not the same size. Greater taper and ovality as 0. 8mm, the wear is greater than 0. 35 ^ 0. 4mm, can not continue to be used. Cylinder repair is usually the standard size diameter increased 0. 25mm size as a primary repair, increase when 1. 5-2mm then scrapped.

Cylinder liner wear law, as shown in Figure 2.19

Normal wear of the cylinder liner, Fig 2. 19 (a) above. Maximum wear position of the first piston ring of the piston is located near the top dead center, because there the highest temperature, the maximum frictional force, dust from the top with the air intake, the coke is also produced in the upper, even the most wear, the central second, the lower the minimum.

Between the piston and cylinder wall lubrication oil is supplied to the cylinder wall from the bottom up, the hard particles of heavier impurities, mostly attached to the cylinder liner lower portion, the lower the severe wear. Wear due to impurities in the oil, as 2. 19 (c) in Fig.

Cylinder liners and piston rings sliding at high temperatures and poor lubrication, resulting in melting of wear, as shown in 2. 19 (d) below.

Figure 2. 19 (e) is vulcanized wear and corrosion conditions caused by the cooling water temperature is too low.

In summary, due to the high temperature side cylinder wall, poor lubrication, piston pressure, lower than the upper easy to wear, and because of the influence of the side pressure, severe wear than the left-right direction of the longitudinal direction, with the result that the inner wall of the cylinder barrel painted oval-shaped and conical form.

To reduce the cylinder liner wear, when using diesel engines, should pay attention to the following points.

1 when the cold start, you should turn the crank disc 2 - 3 laps, so that the inner surface of the liner lubricated.

2 Press selection of oil specified by the manufacturer, and strictly filtered, and keep the proper amount of oil, oil filters cleaned regularly.

3. Regular cleaning of the air filter.

4 Keep the diesel engine in the normal temperature range.

After 5 after replacing piston rings or cylinder liners or newly installed engine must be running, in order to throw people running.