Performing fatigue analysis in PV Elite is a simple process. Let us go through these steps to get your fatigue information into PV Elite.
Open up the ‘Load Cases’ tab by clicking on this tab, as shown below:
Once the Load Cases tab is active, click on the button that is next to ‘Fatigue Analysis’ and the Fatigue Pressure/Cycle Data Input screen appears. In the box at the top called ‘Number of Fatigue Case to Process’ enter the number of cases you want considered, then enter the the pressure range and number of cycles for each range, after which you click on the button at the bottom of the screen that says ‘Save Cases and Exit’. At this point PV Elite has all the information it needs to perform the fatigue analysis on any nozzles you add to your model.
Get back to the General Data Input tab where you find your model on the screen. When you add a nozzle to the vessel using the usual nozzle input screen, notice that at the bottom of screen the check box ‘Perform Fatigue Calc’. Make sure this box is checked, see below:
Now, for the PD5500 and EN13445 models, the drop down list labeled ‘Weld Class’ to the next of the check box becomes active. Choose a suitable letter (see PD 5500 Annex C for details concerning fatigue classes). Note, class C is the least sever, and W the most severe. Enter the rest of your nozzle data, ensuring the nozzle is adequately reinforced in the normal way.
When you have finished entering your vessel data, and have completed building your model, when you press the calculation button (running man), the output processor will include a fatigue analysis report. That report will contain the full analysis for all the nozzles that you indicated to perform fatigue analysis on:
