API 650

Table 5-21 to calculate the anchors refers to appendix F for P (design pressure), Pf (failure pressure) and Pt (test pressure).

F.7.5 tells you to multiply the design pressure and failure pressure by 1.5 and the test pressure by 1.25.

I get extremely high values for the failure pressure.

3 questions:
- Is this 1.5 in table 5-21 for the failure pressure the same as the one in appendix F? (What means that I don't have to multiply Pf by 1.5 before filling it in into te formula)

- If this is the case, is the 1.5 for the design pressure and the 1.25 for the test pressure also included in the formulas of table 5-21?

- Do this factors also apply if the temperature is higher and you need appendix M?

Thank you

1) The values from Appendix F are substituted directly into the equations in Table 5-21. The multipliers you reference are applied in F.7.5 as an increase factor to the failure pressure. The failure pressure is not increased by 1.5, so therefore the 1.5 in Table 5-21 is also applicable.

2) Again for F.7.5, the 1.25 multiplier is applied with the failure pressure. Where do you see a 1.25 multiplier in Table 5-21?

3) I believe these factors in F.7.5 would apply regardless of the status of Appendix M.