Problem 3-45 Design the piston rod of the cylinder at FB of the - PDF document

Problem 3-45 Design the piston rod of the cylinder at FB of the hydraulic floor crane problem 2-80. Select both the material and the factor of safety. The rated crane load is 0.5 ton. Law of Cosine 2 2 2 a b c 2 b c cos ( ) A = + − 2 2 ( )( ) ( ) 18 38 2 18 38 cos 58.87 a 32.57 = + − → = Law of Sine sin ( 58.87 ) sin ( ) α α 28.23 = ⇒ = 32.87 18

Problem 3-45 Cont Design the piston rod of the cylinder at FB of the hydraulic floor crane problem 2-80. Select both the material and the factor of safety. The rated crane load is 0.5 ton. 36.7’’ 17.3’’ C 5’’ ( ) F Fcos 76.77 x = 1000 lbs F y = Fsin ( 76.77 ) + ∑ M 0 = C ( ) ( ( ) )( ) ( ( ) )( ) 1000 54 F sin 76.77 17.3 F cos 76.77 5 0 − − = ( ) 1000 54 F = 17.985 9 18 36 Use: n=4 , UNS G-10400 cold drawn steel (Sy = 71 kpsi) B.C’s: One end Fixed, one end rounded & guided C=1.2 P cr ( ) n P n P 4 3003 12,012lbs = ⇒ = = = cr P 2 2 4 C π EI C π E π D P = = cr 2 2 ( ) L L 64 2 P L ( 64 ) cr D = 4 3 C π E

Problem 3-45 Cont L 25 25 123.46 = = = d 0.81 k 4 4 ) ( )( ) 2 ( )( 2 6 L 2 C π E 2 1 . 2 π 30 10 × ' $ 100.04 = = = % " k S 71000 & # 1 y L L ' $ ∴ Since Euler Column > ⇒ % " k k & # 1 ∴ 7 D 0.81 nearest Standard size is ' ' = 8