ng safety factor based on surface fatigue(pitting)

Textbook: Mechanical Design of Machine Elements and Machines, Second Edition, by Jack A. Collins, Henry Busby, and George Staab, John Wiley & Sons, 2010Problem 15.37A 10-pitch 20 degree full depth involute gearset, with Qv=10 and face width of 1.25inches, is being propsed to provide a 2:1 spped reduction for a conveyork drive unit. The 10 tooth pinion is to be driven by a 15hp 1725tpm electric moter operating steadily at full rated power. A very lonh life is desired for this gearset, and a realibility of 99 percent is required.a. Using AGMA refined approach, calculate the surface fatigue contact stress for the meshing gear teeth.b. If the proposed material for both gears is AISI 4620 steel, and the teeth are carburized and case hardened (not including the root fillet) to a hardness of approximately RC = 60, maintaining the 99 percent reliability requirement, determine the AGMA surface fatigue strength (pitting resistane) for the caburized and case-hardened gear teethc. Extimate the existing safety factor based on surface fatigue(pitting)