Answer:

This is a defect which has been logged in the system and would be resolved in the future release.

Example: Observe that the allowable stress field is blank and hence the user has filled out user defined allowable field in the tube material properties in tubesheet dialog box:

However, when the calculation is performed due the above defect the error message is still issued:

There is no safety factor defined for EN material for Copper alloys (brass is a copper alloy) as you can see in the report and the software is ignoring the user defined allowable stress due to the defect stated above:

The workaround for this is to enter the safety factor in the user defined safety factor for this material type (which is a Copper alloy in this case).

Enter the safety factor for the material type (Copper alloy) eg. 3.5:

Make sure that you enter the safety factor for both chambers 1 and 2 since this is tube material:

Now recalculate and the program now calculates without issuing that error anymore.

The Allowable Stress field in tube material tab is also now updated: