The piston can be divided into 3 parts: piston
bolt assembly, piston head and piston skirt.
The main function of the piston
is to withstand the combustion pressure in the cylinder, and the force through
the piston pin and connecting rod to the crankshaft.
The piston is part of the
combustion chamber, which is often made into different shapes, the gasoline
engine piston by at most flat or concave, so that the combustion chamber has the
advantages of compact structure, small cooling area, the manufacturing process
is simple. The convex head piston used in the two stroke gasoline engine. Diesel
engine piston top often prepared into various pits.
The piston head is the
seat of the part above the piston pin, piston head of the piston ring, to
prevent the high temperature, high pressure gas into the crankcase, and prevent
oil from entering the combustion chamber; the top of the piston absorbed most of
the heat also passed to the cylinder through the piston head, and then through
the cooling medium.









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