البترول والو معة الملك I King Fahd University of Petroleum & Minerals College of Engineering Sciences Mechanical Engineering Department Term Project This project is focused on shaft design and design of bolted joints involving knowledge of load analysis, failure theories, fatigue loading, and shaft design. In this project, you will design a power transfer device (simplified gearbox) with a minimum factor of safety of 2 (under all loading conditions) as shown below. Shaft 1 G1 Gears Flywheel Bearings G2 Shaft 2 A B DEF Both shafts are shrink fitted on the bearings in the gear box chamber as shown in the figure. For consistency, cylindrical roller bearings with same inner diameter (d1) are used on location B and D for Shaft 1. Similarly, cylindrical roller bearings with same inner diameter (d2) are used on location B and D for Shaft 2. The corresponding distances are given below: Distance 0.05 m Location AB BC 0.02 m CD 0.05 m DE DF 0.02 m 0.04 m Shaft 1 and 2 have gears with gear ratio (G1/G2) of 0.5 between them to increase the output torque. In addition, all members (bearings and gear) of Shaft 2 are press-fitted resulting in a consistent diameter throughout the shaft. The gear on shaft 1 is held by a shoulder and retaining ring where the retaining ring is between B and C. The power transfer device is attached to an engine which transmits 150 HP at w₁ = 4000 rpm on point A on Shaft 1. In addition, a 20 Kg flywheel is also attached on Shaft 1 for power storage (due to torque) at point E. The loads (Weight and Torque) experienced by Shaft 1 due to the flywheel should be considered in the analysis. The diameter of G1 (d1) is given as 0.04 m with a pressure angle (a) of 20° resulting in a tangential force (Ft - perpendicular to the paper) and radial force (Fr) where Fr = Ft tan(a). It is noted that no power is lost during torque transfer from G1 (T1) to G2 (T2) such as T1W1=T2W1 and w1/w2=d2/d1. Project Requirements All parts of the project should be typed using word processor (Microsoft Word, LaTeX etc). All graphs should also be drawn using Microsoft Excel etc. Hand written reports or figures will be penalized. Task Marks 1. Sketch layout for Shaft 1 and Shaft 2 separately. Show all shaft components, pulleys, gears, bearings, keyways, grooves etc 10 2. Perform preliminary analysis to calculate: Diameter of G2 Torque on G1 and G2 Tangential and radial forces on G1 and G2 10 In this project, there are forces in 2 planes. 3. Draw free body diagrams showing all the forces, moments, torques for both shafts separately 5 4. Draw shear force and bending moment diagrams for both shafts 5 5. Draw resulting bending moment diagrams for shafts 1 and 2 5 6. Draw torque diagram for shaft 1 5 7. Re-draw a simplified free body diagram and identify (circle) possible critical locations for shafts 1 and 2. Provide reasons for why you chose those locations. 10 8. Perform conservative design for Shaft 2 using Goodman. Due to high price of stronger materials, this shaft should be designed with 1020 CD. Give final diameter of shaft 2. 10 9. Perform shaft design for Shaft 1 using iterative approach. Use 1020 CD as the starting material. Please show your analysis with the shoulder for G1. 10 10. If 1020 CD is not a good material, please show your analysis using 1050 CD for the modified analysis 11. Check factor of safety at other possible critical locations (shoulders, groove, key, etc) - take corrective action if needed (use 1095 HR steel - please show all steps) – Retaining ring design/groove design will be finalized in the next step. 12. Select an appropriate retaining ring using datasheet from https://www.asraymond.com/external-retaining-rings/CE143 - Take corrective actions if needed. Assume r = 0.25 and q = qshear = 0.65. 13. Report the final Shaft 1 diameters 10 10 10 5 5