D 491 10 3 n mm 8 8 we also know that maximum bending

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 35 = 21 mm Ans. Let the piston pin be made of heat treated alloy steel for which the bending stress ( σ b )may be taken as 140 MPa. Now let us check the induced bending stress in the pin. We know that maximum bending moment at the centre of the pin, 39 275 × 100 P .D = = 491 × 10 3 N-mm 8 8 We also know that maximum bending moment (M), M= (d0 )4 − (di )4 π (35)4 − (21) 4 σb = σb = 3664 σb 32 35 d0 3 / 3664 = 134 N/mm2 or MPa σ b = 491 × 10 ∴ Since the induced bending stress in the pin is less than the permissible value of 140 MPa (i.e. 140 N/mm2), therefore, the dimensions for the pin as calculated above (i.e. d0 = 35 mm and di = 21 mm) are satisfactory. 491 × 103 = π 32 Fan blows air over engine to cool it Air filter stops dust and dirt from being sucked into engine Driveshaft Disk brake Spark plug Twin rotors German engineer Fleix Wankel (1902-88) built a rotary engine in 1957. A triangular piston turns inside a chamber through the combustion cycle. 1144 n A Textbook of Machine Design 32.13 Connecting R...
View Full Document

Ask a homework question - tutors are online