Third Design Project University of Wisconsin – Madison Abstract For this design project I was required to design a shaft for a water turbine that must deliver power to an electric generator and also to a bucket elevator for carrying grain to a hopper while meeting the criteria given to me by my boss. I was given some initial values and am supposed to place two bearings B and D to support the shaft to meet the criteria given. Design Criteria Shown below is the diagram I was given to find the placement of bearings B and D. I was given that the total bending load on the shaft at the sprocket C is 815 lb, and the driven side of the chain is oriented at an angle of 40 deg from the vertical. At gear E, Which drives the generator, the bending forces on the shaft are 494 lb in the y-direction, and 180 lb in the x-direction.
Also the flat belt pulley A which drives the elevator, the maximum allowable tension in the belt is 417 lb. The belt will be parallel on either side of the pulley, and oriented at an angel of 60 deg. from the horizontal. The coefficient of static friction between the belt and the pulley is.
35. The bending load exerted by the pulley is equal to the sum of the tensions on either side of the pulley. When solving, draw the shear and bending moment diagrams for the x and y direction. The bending moment and any point will then be equal to sort (Mh ^2 + Mv 62).
To achieve the project objective, the test rig structure must be design and suitable for place the archery testing apparatus. We need to develop tools that can test the efficiency in archery equipment. The arrows were made of pine and consisted of a main shaft and about 15–20 centimeter (6–8 inches) long fore shaft with a flint point. This led the commercial development of new forms of bow ...
The bending moments at the two bearings was not to exceed 3500 lb-in. and the bending moment at C was not to exceed 5000 lb-in.
Design Solution and Conclusion To solve I set up my known’s in section A of the appendix using the equation to find t 1 I solved and found T 1 to be 138. 87 lb. Then I added T 1 and T 2 together to find T total which was 555. 87 lb. From finding this I was able to then find Ay which was 481.
41 lb and Ax that was 227. 9 lb (Section B) Then I also solved for Cx which was 523. 87 lb and Cy which was 624. 33 lb. Using lengths of 6 for distances of my bearings from c I then drew separate diagrams for x and y (section c) Then in Section D of the appendix I solved for the moments about By and Bx and found Dy = 188. 13 lb and Dx = 393 lb using those values I solved for the equilibrium of The forces in the x and y directions and found By = 162.
938 lb and Bx = 588. 785 lb. Now having solved for all the unknowns I set up my shear diagrams and the by finding the area of the boxes in the shear diagrams I drew my moment diagrams all in Section F of the appendix. Then I found my bending moments at B and D and my Bending moments at which were all within the design criteria (Section E).
ReferencesPlesha M. (2003) A Short Guide to Technical Writing, UW MadisonPlesha M.
(2003) Design Overview, UW Madison.