Unformatted text preview: ngs may be determined by using the following expression
F = π D · tR · nR · pR · µ
where D = Cylinder bore,
tR = Axial width of rings, * B.M. due to variable force from 0 to m1 ω2 r × x is equal to the area of triangle multiplied by the distance x of C.G. from X − X i.e. . 3 l 1150 n A Textbook of Machine Design nR = Number of rings,
pR = Pressure of rings (0.025 to 0.04 N/mm2), and
µ = Coefficient of friction (about 0.1).
Since the frictional force of the piston rings is usually very small, therefore, it may be
The friction of the piston is produced by the normal component of the piston pressure which
varies from 3 to 10 percent of the piston pressure. If the coefficient of friction is about 0.05 to 0.06,
then the frictional force due to piston will be about 0.5 to 0.6 of the piston pressure, which is very low.
Thus, the frictional force due to piston is also neglected.
4. Force due to friction of the piston pin bearing and crankpin bearing
The force due to friction of the piston pin bearing and crankpin bearing, is to bend the connect...
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- Spring '11
- Combustion, Internal combustion engine, pistons, Connecting rod, Engine technology, piston pin