Calculating Nozzle Loads

[nborders]

What procedure do some of you use to calculate nozzle loads on a tangential nozzle?

On a tangential I'm referring to a nozzle at 90 degrees in the orientation view but it is parallel to the 0 degrees and 180 degrees.

Thanks in advance

 

[bagarbilla]

Check ASME Boiler and Pressure Vessel Codes..Or any book which have simpler explanation of the ASME code

 

[MJCronin]

borders...

When you state "calculate nozzle loads", are you trying to evaluate the strength of a nozzle on vessel or tank or...

Are you trying to develop the loads that will be used for an evaluation of a nozzle?

I sure would be great if the posters mastered not only entry level skills in English, but also a little bit of diction......

-MJC

 

[jte]

A question which will get far better response in forum794.

ASME provides no guidance.

Develop the piping loads using your piping model either by hand if reasonably simple or by a program such as Caesar II.

You could use WRC-107 as a rough check: Take the nominal opening diameter as the nozzle diameter since it is small. The cut in the circumferential direction will be much larger - and the loads distributed over a smaller area, so small is conservative. Translate the loadings to a coordinate system normal to the vessel: Longitudinal loads in the pipe are shear loads on the vessel, etc.

Realistically, this opening will likely have a relatively large repad or insert plate, and chances are that the pipe loads will not be too problematic. I suspect the longitudinal moment (relative to the vessel, i.e. the moment which tends to push a vertical vessel over) will be the greatest cause of concern.

To get a realistic answer... You'll need to perform an FEA.

jt

 

[mizzoueng]

WRC-107 can be used for nozzle calcs on parallel and horizontal nozzles on vessels. You can use it for tangential nozzles as well up to a point.

Refer to WRC-107 and WRC-297 for both calculations. WRC-107 limits the vessel axis to tangent distance to a point, WRC-297 extends this out to a true vessel OD tangent and sometimes beyond.

I use WinNOZL for those calculations, but you need to use a program like Ceaser II, AutoPIPE, CAEpipe, etc first to calculate the loads at the nozzle connection point.

 

[racookpe1978]

Regardless of the orientaiton of the nozzle, the piping and support deigners should attempt to prevent any nozzle loading from occuring.

Doesn't happen (can't happen !!) in the real world with real budgets and real schedules, but one can dream.

I suspect, but cannot prove, that original poster was asking about nozzles that would create tangential flow, not radial flow, into the tank or PV. But such a nozzle would create even less stress than a radial nozzle because it intersects the tank with an ellipse, not a ring, and has more weld material to resist stress: so ... I'm puzzled.

 

[MJCronin]

Well.....we can all keep guessing about the original question.

The poster of the original question either has his answer from another source or simply does not seem to feel that he owes us the respect of a response in English.

English and a fundamental grasp of diction.... still rocks.

-MJC

 

[mizzoueng]

racoopke,

I think he may be asking about that as well. Nozzles that far out do reduce the amount of stress seen on the vessel and the nozzle itself thanks to the longer welds and the surface area.

But WRC-107 does not allow for this type of nozzle over a certain R/t (vessel radius/thickness) ratio and WRC-297 does.

 

[nborders]

"I suspect, but cannot prove, that original poster was asking about nozzles that would create tangential flow, not radial flow, into the tank or PV. But such a nozzle would create even less stress than a radial nozzle because it intersects the tank with an ellipse, not a ring, and has more weld material to resist stress: so ... I'm puzzled."

You are correct I was talking about creating a tangential flow.

Also I did get my answer. Thanks again for all the replies.