Nozzle external projection

[kdviator]

When nozzle is offset from center line for example vessel is 114' ID and 1 1/2 nozzle is offset from center line of vessel 4'-3". If call out in vessel nozzle schedule is 12 3/4" external project, this should be from center line of nozzle, long point of nozzle, or short point of nozzl.
Thank You in advance.
Regard
kdviator

 

[jte]

kdviator-

There is no standard. Based on my biases and with no further info, I'd assume the 12¾" projection would be from the "work point" at the intersection of the centerline of the nozzle and the ID of the vessel. I'd prefer to see the dimension called out as a distance from the centerline of the vessel to the face of flange.

jt

 

[NozzleTwister]

kdviator,

I'm not a vessel man but I do use those drawings almost daily.

Nozzle projection from the vessel centerline is the norm for a number of reasons, including the possible confusion you describe.

NozzleTwister
Houston, Texas

 

[unclesyd]

I agree with the above about working from the centerline if at all possible, but in some cases it gets a little difficult, like a hillside or tangential nozzle. In this case one has to give some reference that is readily attainable with the normal fabricators tools, angle from a witness mark, elevation form a clear reference, and on most nozzles the short side difference to flange face.

If there is a difficult nozzle location just make sure your have a shop workable reference.

 

[waskillywabbit]

Nozzle projection from the centerline is the norm...but we always state that on our drawings in the general notes. We also do not list projections in the nozzle schedule for this reason, we show them on the elevation/orientation views. The old addage "A picture is worth more than a thousand words" still holds true...



Brian

 

[JStephen]

I would take it to mean distance on centerline of the nozzle, from the OUTside of the shell (not the repad, not the inside of shell). If it's not critical, it shouldn't matter. If it is critical, it should be shown clearly.

 

[kdviator]

I thank all for your input, I was just checking my knowledge before sending e-mail out to info engineering.
I love this group, very useful tool.