Unformatted text preview: l1 P.D
8 Fig. 32.8 ...(iii) 1140 n A Textbook of Machine Design We have already discussed that the piston pin is made hollow. Let d0 and di be the outside and
inside diameters of the piston pin. We know that the section modulus, π ( d 0 ) 4 − ( di ) 4 Z = 32 d0 We know that maximum bending moment,
π ( d 0 ) 4 − ( di ) 4 σb
M = Z × σb = 32 d0 where
σb = Allowable bending stress for the material of the piston pin. It is
usually taken as 84 MPa for case hardened carbon steel and
140 MPa for heat treated alloy steel.
Assuming di = 0.6 d0, the induced bending stress in the piston pin may be checked.
Spring Cam chain is driven by
pushed round by
Waste gases out Valve Carburettor
Piston Fuel flows in when
needle rises Crankshaft
Fuel in Another view of a single cylinder 4-stroke petrol engine. Example 32.2. Design a cast iron piston for a single acting four stroke engine for the following
Cylinder bore = 100 mm ; Stroke = 125 mm ;...
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- Spring '11
- Combustion, Internal combustion engine, pistons, Connecting rod, Engine technology, piston pin