What is the code case that allows the center 80% of an elliptical and torrispherical head to be calculated as a hemispherical head?
API 510 allows it in para 7.4.6, ASME infers it in the nozzle calc in UG37, and API 579 has it in their head calcs in para 2C.3.5 and 2c.3.6... but I cannot find...
In Section 5.12.4 - Compression Rings, a definition for T2s is given and refers to Section 5.10.
I cannot find where it is referenced in 5.10.
T2s is used in equation 5.12.4.3 - eq. 26
Is there an equation for the contributing length for the bottom plate (Xbtm)? It looks like it is not included in the text, and in the example (step 17), they mistakenly pasted the calculation for Xshell.
In the definition for "Wind" (Section 5.2.1.j), is the shape factor already included in the pressure? For a cylindrical shell, it is typically 0.67.
Also, where does the 18lbf/ft^2 come from... because when I check ASCE 7, I can't find that number anywhere.
