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5.7 ASME Sec III Appendices

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If ASME Sec III Appendices is selected in the Fatigue model/code drop-down menu in Project Setup dialog box in 5.1 Data Entry and Project Setup, the ASME Sec III Appendices button  on the toolbar becomes activated. 


Choose Input>ASME Sec III Appendices or click ASME Sec III Appendices button.  The ASME Sec III Appendices Data Input dialog box appears. 



5.7.1 Selecting Material


Select a material from Spec No. drop-down menu.



5.7.2 Sn : Sp Ratio



Sn = primary + secondary stress (Pm + PL + Pb + Q)


Sp = primary + secondary + peak stress (Pm + PL + Pb + Q + F)


It is required that entered stresses be Sp so that Sn is derived from Sp by Sn:Sp ratio (<= 1.0). Leaving Sn:Sp ratio = 1.0 is conservative.


5.7.3 Fatigue-Strength-Reduction Factor



The default value of weld surface fatigue-strength-reduction factor Kf is 1.0.  Enter an appropriate value to replace the default value.  If not sure which value is appropriate, click Reference button to see the most common cases.



5.7.4 Selecting Fatigue Curve


The program automatically select a fatigue curve according to the user selected material.  The suggested fatigue is displayed in the Selected fatigue curve information box.



If you are not satisfied with the selection, click Change button to select another fatigue curve from the following pop-up dialog window.



Click OK button to confirm and return to previous window.  Click Cancel button to ignore the change.


Click Plot fatigue curve button.  The Fatigue Curve window appears.  You can zoom, print or export the chart, or change the styles of the chart by clicking the buttons on the tool bar.  Click X button on the upper-right corner to close the window.  The following is an example.



When completed, click OK button to confirm and return to the main window.






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