API 620 Flush-Type Shell Connection - Area Coefficient

[Andrewdroth]

Hi all,

I'm having trouble with "Figure 5-13 Design Factors for Flush-Type Connections" were the values on the vertical axis of the chart are defined by the equation [(H+29)D+770]385h.

The values on the vertical axis range from 0 to 1.25.

I can not seem to achieve such low values with the formula as is.

The values I'm using are as follows.

H=Height of tank, in feet(29')
D=Inside diameter of tank, in feet(25')
h=(I've assumed)Vertical height of clear opening, in in(4").

Perhaps the formula should read [(H+29)D+770]/385h?

Any help would be appreciated.
Andrew

 

[JStephen]

Isn't that same chart in API-650? If so, check it there.

Also, they have a fairly new addendum out on API-620, you might check it.