ASME Patran Plug-in

ASME Utility usage guide

When the ASME utility is started by selecting the ASME icon, the form as shown on the right comes up.asme1

Common data entries:
Below is the list of data entries used for all three methods of using the utility. The parts that differ will be described separately.

Number of interpolation points
The number of points through the thickness of the plate that the stress will be extracted at and used to calculate the stress-classification lines.

Coordinate frame
The coordinate system in which the stress components will be extracted. The Sxx to Szx results will be in this coordinate frame.

Select results
This is where the result-case and result is selected for use in the utility.

FEA results to plot
Plots the interpolated results at all locations along the line used. The Stress components as well as the Tresca result can be selected.

Linearized results to plot
Plots the linearized results for the stress components and Tresca.

Clear graphs
Whenever graph windows created by the ASME utility exist, this will delete the curves and the graph windows. For the single-line and surface methods, you can plot results again after pressing this button because the results are still available to the utility.

Closeasme2
This will close the ASME utility form, but it will not delete the graphs. Unless you have closed and re-opened Patran, you will be able to open the utility and clear graphs or plot results as long as results are still available (i.e. the last operation was not a multi-line calculation).

Results form
The results form is as shown on the right.

The temperature field is used to calculate the average temperature through the thickness of the plate. This is done to help the user determine which limit-line should be used.


Methods of use:

Single line
If a stress classification is to be performed on a single line, the “Method” should be set to “Line” and the curve selected in the “First curve” data-box. At this point the active “FEA Results to plot” area is not used.
After selecting the result and the curve, press the “Calculate” button. Both the “FEA results to plot” and the “Linearized results to plot” will become active. At this point, the data is calculated and will be available to plot. Select the results you want to view and press the “Plot results” button.

A separate graph window will appear for every type of result selected. The same result direction (or Tresca) will be shown in one graph for the stress classification results and the actual data if both are selected. (See below)

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The meaning of the curve names are as follows:
  • Sxx to Szx is the stress component in direction xx to zx.
  • Act and Actual is the value as interpolated at the interpolation points of the curve
  • M is the linearized membrane stress
  • M+B is the combined membrane and bending of the linearized stress.
  • Sa and Sb are the stresses at the start and end of the curve
  • Limit lines are the limit values as specified in the “limit values” entry boxes:
    • “S” is for secondary limit line
    • “M” for primary membrane
    • “M+B” for Membrane and bending combined

Multiple lines
If the “Method” is set to “Line” and more than one curve is selected, the “FEA results to plot” determines which results will be shown for all of the curves. No linearization will take place.

This is done to determine which curves are valid for use in the linearization procedure. For every curve, a separate graph window will be drawn which shows the through-thickness stress component for all the components selected (Sxx to Szz). (See below)

If Tresca is selected, a separate graph of Tresca-stress will be shown on a separate graph for all the curves combined.

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Surface method
The surface method does a stress classification surface calculation instead of a stress classification line. What this does is to average the stress components at every layer and to use this average values to perform a linearization.
To activate it, switch the “Method” to surface and select two parallel curves: One in the “First curve” and the other in the “Second curve”. The linearization will take place in the curve direction (i.e. the curve is through the thickness of the component). The averaging per layer will be done on a surface extruded between the 2 curves.

Results are treated in the same way as for the “Single curve” method: Select the components and press the “Plot results” button.