Nozzle reinforcing questions- Section VIII Div. 1
Nozzle reinforcing questions- Section VIII Div. 1
(OP)
First Question: Section VIII defines the "limits of reinforcement", but the definitions become somewhat ambiguous when applied to curved plate. Are the limiting lines assumed to be parallel to each other, or normal to the tank surface? If normal, are the limits measured from one point, or from varying points depending on the radius? See the attached sketch to see what I mean. This won't affect calculated area so much, but does affect whether the reinforcing area extends into the knuckle of a head or not.
Second Question: Where the shell-to-nozzle connection is not a full-penetration weld, there will be some gap between the nozzle wall and the shell. Is this gap limited or accounted for in any way?
Thanks!
Second Question: Where the shell-to-nozzle connection is not a full-penetration weld, there will be some gap between the nozzle wall and the shell. Is this gap limited or accounted for in any way?
Thanks!





RE: Nozzle reinforcing questions- Section VIII Div. 1
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RE: Nozzle reinforcing questions- Section VIII Div. 1
You are not restricted from having a repad extend from the shell to the knuckle or vice versa.
See Interpretation VIII-1-89-83.
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RE: Nozzle reinforcing questions- Section VIII Div. 1
And of course the motivation in keeping the area out of the knuckle is to use the reduced crown thickness.
RE: Nozzle reinforcing questions- Section VIII Div. 1
I think this one is in accordance to code because:
-d is to be taken at mid surface as specified by UG-37
-as the main limit for reinforcement is based on d it would be inconsistent to measure the limit on a different plane
prex
http://www.xcalcs.com : Online engineering calculations
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RE: Nozzle reinforcing questions- Section VIII Div. 1
Where Fig. C came from- there is also a requirement that you have the same amount of reinforcing on each side of the opening. Originally, I drew the repad so it was centered over the intersection of nozzle and required-thickness, which made it obviously unbalanced. And I assume the repad would be centered on the neck when installed, anyway. But also, if all limits are measured from the center of nozzle/ center of required thickness, then the "excess plate thickness" will be unbalanced for a hillsided nozzle. So it would make sense to me if at each radius, the limit was taken from the nozzle axis, although this is not stated anywhere in the code.
RE: Nozzle reinforcing questions- Section VIII Div. 1
Another way of looking at it is that you should check the compensation on one side only of the opening at the most unfavourable angular position, using of course half of the required compensation.
prex
http://www.xcalcs.com : Online engineering calculations
http://www.megamag.it : Magnetic brakes and launchers for fun rides
http://www.levitans.com : Air bearing pads