Assume gears are readily available in face-width increments of 0.5 in (i. e. 2.0 in, 2.5 in. 3.0 in, 3.5 in.), with face widths in the range of three to five times the circular pitch. Specify a diametral pitch and face width such that the minimum WEAR factor of safety for the pinion is equal to 1.3.

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]