Hi to all,
I am doing analysis of Turbine Drain Line, that work is in Our scope,
And client is asking me to use NEMA SM23 for nozzle qualification.

but in NEMA SM23 one has to do Individual plus combined check for nozzle qualification.

But i dont have any information for other nozzles of turbine,
Basically that is not in our scope.

Now How can i use NEMA SM 23.
Can we use NEAM SM 24, i herd it gives allowable for individual nozzle.
I need urgent reply.

Thanks in Advance
With Regards
Aditya Singh

Dear Adi singh,

What is the size, temperature, pressure of that drain line? Read point 1 of chapter X of Sam Kannappn book in "section piping system to be anlyzed" or other point related. If you still want to calculate based that criteria, of course you need the info of the biggest size of nozzle connected to turbine and the line connected to its nozzle to perform loads check.

lines are small bore line
but the temperature is more than 600 C
moreover occational forces( wind/earthquake) are the major problem at site.

600 deg C is very high temp. I think that line needs flexibility analysis and individual load check at its nozzle connection. But if drain line size is different significantly w/ the biggest nozzle, I am not sure if you need the combine load check of both instead of combine of inlet and exhaust nozzles only. Since the equipment too rigid for that small bore line. But for sure, include also at least the biggest nozzle load in combine load check.

What are the size of those drain , inlet, and exhaust lines of the turbine actually?

Hi Adi Singh,

I am interested w/ that drain line. So please answer my Q above . I have one more idea by not including the pipe connected to the biggest nozzle. Assume the load acting on the biggest nozzle = individula allowbale nozzle load as per related standard/specification (conservative, but actually may lower). Then combine w/ load generated by the drain line. If it pass, the overall load check pass. How do you think?

hello
Actually i am doing analysis of a Hot Reheat line 24inch 572Degc39bar press

of boiler at saftey valve discharge my boiler vendor has given a horizontal force of 20KN to be act at the saftey valve discharge also the vertical force will be 2oKN while applying the both in Operating + Saftey relive valve case i found the straess in occasional condition goes high that is 97% i want to limit it by 85% .

Can any one tell me as per my knowldge 20KN load in the horizontal direction in saftey vale discharge is too high also tell me how to reduce the stress at the stub on which saftey valve is mounted i have already tried this with fabricated TEE still it fails in stress i cant put Reinforce pad because its P-91 material please help me

Nice IdeA samual

Dear Adi Singh,

Yes, 20 kN = 20,000 N is a big force. You can imagine as picking up 2 ton of something on your shoulder . I have never involved to that line. But for that size it may be relevant. To make sure you may ask their (vendor) calculation or their such related documents.

Have you try using stopper support over there or add some flexibility. Like adding loop to reduce axial force in straight line due to temperature. Hope this works (my guess). I agree w/ you to put it as OCC load case.

There is a good reference API RP 520 to calculate discharge force of PSV during PSV popping for gas fluid. Check it out. May be the supporting method and adding flexibility at discharge line typically for PSV line works also for above case.

I mean "Like adding loop to reduce axial force in straight line "AT THE END OF THE LINE not along it" due to temperature.