A 22-tooth pinion rotating at 1650 rpm meshes with a 66-tooth gear in a spur gear reducer. Both pinion and gear are manufactured to a quality level of 10. A reliability of 0.9 has been specified, and the transmitted tangential load is 5000 lb. Conditions are such that Km = 1.7. It is proposed that standard 25°, full-depth teeth be used, with both pinion and gear hobbed from an AISI 4340 nitrided steel. The diametral pitch is 5, and the face width 2.500 in. Estimate the number of cycles of contact (surface) stress (using the AGMA equations) that the gearset can withstand.
