The cylinder of the internal combustion engine is the working chamber of the volumetric displacement. During engine operation, the internal and external parts of the cylinders experience different heating.
- The inside part of the cylinder is a sleeve or cylinder liner.
- The outer part of cylinder is the motor cooling jacket.
Engine cylinder schemes
a – without cylinder liner, but with short insert; b, c – with wet cylinder liner; d – with wet cylinder liner and short insert; 1 – Cylinder block; 2 – motor cooling jacket; 3 – insert; 4 – cylinder liner; 5 – seal rings; 6 –
The inner surface of the sleeve or cylinder liner is called a cylinder face. Cylinder face is a working part of the cylinder so it has a special subjected to special processing as honing, chroming or nitrogen case-hardening. There are some types of materials to produce cylinder faces.
There is a special relief on the cylinder face, which helps to reduce friction between the piston, piston rings and the cylinder due to the retention of engine oil on the cylinder walls.
The inner surface of the cylinders of modern engines is subjected to laser whitening remelting, which contributes to the formation of high hardness white cast iron. The resource of such cylinders is higher and does not require repair dimensions.
Cylinder liners are casting from high strength cast iron or special steels. Sometimes aluminum cylinder liners are plating with chrome. In engine, where the crankshaft rotates unevenly, the flywheel must have a large moment of inertia. The rotation of the crankshaft in a multi-cylinder engine occurs more uniformly, since the working strokes in the various cylinders do not coincide with each other. The more cylinders the engine has, the better evenly the crankshaft rotates. The load on the parts of the crank mechanism in a multi-cylinder engine changes more smoothly than in a single-cylinder.
Cylinder Liner Defects
The cylinder liners wear out due to friction between the piston and the mirror (inner cylinder wall). As a rule, increased wear may occur by the following reasons:
– Not enough motor oil on the cylinder liners walls;
-engine did not work for a long time, and all the motor oil was drained in the crankcase;
– Use of inappropriate viscosity motor oil;
– The main causing of corrosion is use of water as a coolant;
– Chips and scratches occur due to improper installation, dismantling (all actions for shooting cylinder liners must be carried out according to the rules with a special puller);
– The engine is not used correctly.
Defect processing methods of cylinder
Defects of cylinder are eliminated by processing methods as: grinding, milling, spraying, surfacing and honing.