Applies To
Product(s):	AutoPIPE Vessel
Version(s):	ALL
Area:	Calculations
Date Logged & Current Version	Feb 2025 45.00.03.001

Problem:

How does 'Apply ASME UG-23(d) (20%)' option works?

Solution:

As per ASME Section VIII Div.1 UG-23 (d), general primary membrane stress shall not exceed the 1.2 times the maximum allowable stress permitted.

When the 'No Increased Allowable' option is enabled, the software uses the normal allowable compressive stresses (13.2 MPa) and the exceptional allowable tensile stresses (99 MPa).

Similarly, when the 'Apply ASME UG-23(d) (20%)' option is enabled, the software considers 1.2 times the normal allowable stresses (15.84 MPa for both Tensile and Compressive).

Note : It is commonly accepted that an earthquake is an exceptional case, hence when 'No Increased Allowable' option enabled then allowable tensile stress in Operation with Seismic case is calculated as 0.9*Yield Stress at temperature in this cases (0.9 * 110) = 99 MPa.

This criteria is not applicable for Operation with Wind load case.