A pair of gears with 25?, full-depth, involute teeth transmits125 hp while the pinion rotates at 2500 rpm. The diametral pitch is4, and the quality number is A9. The pinion has 32 teeth and thegear has 76 teeth. The face width is 1.5 in. The input power isfrom a multicylinder gasoline engine, and the drive is for a lowspeed water pump. The drive is a commercial enclosed gear unit.Specify suitable materials for the pinion and the gear. Assume asafety factor of SF=1.25, reliability of 0.90 and a design life of8000 h. After that, determine the power-transmitting capacity forthe pair of gears.
