Stress Allowables for Sec. VIII, Div. 2 Class 1 Vessel 1

[m_ridzon]

From my understanding, ASME.VIII.2 §2.3.3.1 added new categorization for Class 1 and Class 2 vessels in v2017. A Class 1 vessel uses §5 to evaluate stresses. As I understand, §5 uses von Mises stress theory (as opposed to Tresca). However, the stress allowables for a Class 1 vessel are taken from ASME.II.Table 2A, which is "stress intensity," thus inferring Tresca theory. So how does it make sense to use stress intensity allowables for §5 von Mises analysis?

 

[TGS4]

The allowable stress limits in all of the Tables of Section II, Part D, are uniaxial. It is the various design Codes that choose the methods of the invariant to convert multiaxial stresses. Don't overthink it, just use the values.

 

[m_ridzon]

The allowable stress limits in all of the Tables of Section II, Part D, are uniaxial. It is the various design Codes that choose the methods of the invariant to convert multiaxial stresses. Don't overthink it, just use the values.

Perfect. Yah, I thought I might be over-thinking it, but figured some smart folks here could set me straight.

 

[m_ridzon]

It is not a responsible engineering practice to work with an old code edition.

Are you just trolling posts? Go read my reply at this Link