See ASME B31.8 Chapter VIII Section A842 (Strength Considerations), Para. A842.2.2 (Design Against Yielding)...and Caesar II Quick Reference Guide, "Code Stresses / US Code Stresses".
For Topside Offshore Piping (including Risers), Sustained (SUS) and Operating (OPE = P + W + T and OPE = P + W + T + OCC / Wind, U1 etc.) stresses are to be qualified.
For Longitudinal (SL) stress, the F2 = 0.80 factor is used, while for Combined/Equivalent (SE/Se) stress, the F3 = 0.90 factor is used as per ASME B31.8 Table A842.2.2-1.
B31.8 VIII does not provide displacement stress range evaluation, indeed... and there is no discrimination between Sustained, Operating and Occasional loads - the stress limits are invariant as noted above. If you have only one Calculation Temperature (T1), the second group of load cases is written correctly.
Regards,
_________________________
Dorin Daniel Popescu
Lead Piping Stress Engineer