Page 362 - Marks Calculation for Machine Design
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P1: Sanjay
                          January 4, 2005
                 Brown˙C08
        Brown.cls
                  344
                            U.S. Customary 15:14  APPLICATION TO MACHINES  SI/Metric
                        C 2 = 2 (1.0625 in/2) tan 30 ◦     C 2 = 2 (0.027 m/2) tan 30 ◦
                            + 2.5 (0.625 in)                   +2.5 (.016 m)
                          = 2.18 in                          = 0.056 m
                  Therefore,                         Therefore,

                                     lb                                  N
                        (1.814) 30 × 10 6  (0.625 in)     (1.814) 2.07 × 10 11  (.016 m)
                                    in 2                                m 2
                    k 1 =                             k 1 =
                                  0.93 in                           0.024 m
                               ln 5                              ln 5
                                  2.18 in                           0.056 m
                                                                 9
                              7
                        3.40 × 10 lb/in                   6.01 × 10 N/m
                      =                                 =
                           0.758                              0.762
                              7
                                                                9
                      = 4.49 × 10 lb/in                 = 7.88 × 10 N/m
                  Step 9. Substitute the effective depth (h), the  Step 9. Substitute the effective depth (h), the
                  bolt diameter (d bolt ) and the modulus of elastic-  bolt diameter (d bolt ), and the modulus of elastic-
                  ity (E cast iron ) in Eq. (8.22) to find the stiffness  ity (E cast iron ) in Eq. (8.22) to find the stiffness
                  (k 2 ) as                          (k 2 ) as
                                                                       ◦
                                    ◦
                              (π tan 30 ) Ed                     (π tan 30 ) Ed
                       k 2 =                              k 2 =
                                                                       ◦
                                    ◦
                               2 t tan 30 + 0.5 d                2 t tan 30 + 0.5 d
                           ln 5                               ln 5
                                                                       ◦
                                    ◦
                               2 t tan 30 + 2.5 d                2 t tan 30 + 2.5 d
                                 ◦                                 ◦
                           (π tan 30 ) E cast iron d bolt     (π tan 30 ) E cast iron d bolt
                         =                                  =
                                   C 1                                C 1
                                ln 5                               ln 5
                                   C 2                                C 2
                  where                              where
                                  ◦
                                                                     ◦
                        C 1 = 2 t tan 30 + 0.5 d           C 1 = 2 t tan 30 + 0.5 d
                                   ◦                                 ◦
                           = 2 h tan 30 + 0.5 d bolt         = 2 h tan 30 + 0.5 d bolt
                           = 2 (0.3125 in) tan 30 ◦          = 2 (0.008 m) tan 30 ◦
                             +0.5 (0.625 in)                   +0.5 (.016 m)
                           = 0.67 in                         = 0.017 m
                  and                                and
                                  ◦
                                                                     ◦
                        C 2 = 2 t tan 30 + 2.5 d           C 2 = 2 t tan 30 + 2.5 d
                                   ◦                                 ◦
                           = 2 h tan 30 + 2.5 d bolt         = 2 h tan 30 + 2.5 d bolt
                           = 2 (0.3125 in) tan 30 ◦          = 2 (0.008 m) tan 30 ◦
                             + 2.5 (0.625 in)                  + 2.5 (.016 m)
                           = 1.92 in                         = 0.049 m
                  Therefore,                         Therefore,
                                     lb                                 N
                        (1.814) 16 × 10 6  (0.625 in)      (1.814) 1.1 × 10 11  (.016 m)
                                    in 2                                m 2
                    k 2 =                             k 2 =
                                  0.67 in                           0.017 m
                               ln 5                              ln 5
                                  1.92 in                           0.049 m
                                                                 9
                              7
                        1.81 × 10 lb/in                    3.19 × 10 N/m
                      =                                  =
                           0.557                              0.551
                              7
                                                                 9
                      = 3.26 × 10 lb/in                  = 5.80 × 10 N/m
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