_______________________________________________________________________ PROBLEM (9.9) A turbine shaft of diameter d is under a thrust load P and a torque T (Fig. P9.9). Calculate the largest permissible value of the load P if the allowable normal stress is not to exceed Given: σ all = 220 MPa T = 2 kN ⋅ m, d = 60 mm, σ all . SOLUTION y z C A Maximum normal stress occurs at a point A. d We have 16T 16(2 ×103 ) τ= 3= = 47.16 MPa πd π (0.06)3 4P 4P σ= 2= = 353.7 P (P in MN) πd π (0.06)2 Hence σ1 = σ σ + ( ) 2 + τ 2 = σ all 2 2 220 = 176.8 P + (176.8P) 2 + (47.16) 2 (220 − 176.8P) 2 = 31, 258 P 2 + 2, 224 or 48, 400 − 77, 792 P + 31, 258 P 2 = 31, 258 P 2 + 2, 224 Solving, P = 0.594 MN = 594 kN Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted by Sections 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawful.