Machine Design

Use this for “Cast iron with Sᵤₜ = 200 MPa and Suc = 750 MPa carries σ₁ = 60 MPa and σ₃ = −90 MPa. Find n by Coulomb–Mohr.”

Use this for “A 50 mm × 10 mm plate with a 10 mm hole carries 20 kN; Kₜ = 2.5 from the chart. Find the nominal and peak stresses.”

Use this for “A steel part with Sᵤₜ = 600 MPa and Sₑ = 210 MPa sees a fully reversed 300 MPa. How many cycles will it last?”

Use this for “A machined 30 mm steel shaft has Sᵤₜ = 600 MPa. Find kₐ, kb and its endurance limit in rotating bending.”

Use this for “A part runs 20,000 cycles where it would last 80,000, then 100,000 where it would last 500,000. How much of its life is used?”

Use this for “A ball bearing rated C = 30 kN carries 5 kN at 1800 rpm. Find its L₁₀ life in revolutions and in hours.”

Use this for “A ball bearing must carry 4 kN at 1000 rpm for 20,000 h. What catalog rating C should it have?”

Use this for “A disc sags its shaft 0.1 mm at rest. Find the first critical speed in rad/s and in rpm.”

Use this for “A spur pinion (m = 3 mm, face width 30 mm, Y = 0.32) carries Wₜ = 1061 N at V = 4.71 m/s. Find Kᵥ and the bending stress.”

Use this for “Gears of 20, 60, 18 and 54 teeth form a compound train, with 60 and 18 on one shaft. The input turns at 1800 rpm. Find e and the output speed.”

Use this for “An M12 bolt (Aₜ = 84.3 mm², proof strength 600 MPa) is tightened for reuse with K = 0.2. Find the preload and the wrench torque.”