Steam turbine inlet nozzle

Posted by: AVenugopal

Steam turbine inlet nozzle - 03/28/10 09:40 PM

Iam a new entrant to this great forum .
I have no experience with Ceaser. I am a learner. Our piping analysis work is done by our consulatants .
I requet some one to advise how to input the pipe end when it is connected to a steam turbine nozzle. Steam turbine manufacturers usuaally specify his nozzle FX, FY, FZ, MX, MY, MZ and also displacements. Whether these are allowables as per the turbine manufacturer or whether the turbine nozzle itself will have these displacements and exerts the forces and moments on the steam pipe in hot condition. If these are allowables then is it that we calaculate NEMA 23 allowables and compare and adopt which ever is the highest.or if these are forces and moments generated by the turbine how should these inputs be added in to the modelling.

Thanks for your attention.

Best regards

Venugopal

Kindly advise.
Posted by: SBNZ

Re: Steam turbine inlet nozzle - 03/29/10 09:38 PM

Hi Venugopal,

The forces and moments given by the turbine supplier are the "allowables" from piping system. The displacements are the actual movements of the terminal points.

In piping analysis you should, therefore, model the pipe terminal point as an anchor having the thermal displacements as given by the supplier. Your objective would be to design the piping system so that the loads/ moments at that anchor (representing turbine connection) do not exceed the allowables. In most cases, you will struggle to achieve that smile

If supplier's allowables are less than NEMA 23, you do not have to assume the higher value. If they are, however, higher than NEMA 23 and you can not meet his stipulations, you may try by asking him to review the allowables and give reference of NEMA 23. Ultimately, the supplier's data prevail. You have to assume they have more exact methods (FEA) to determine the safe loads for their equipment and must adhere to that.

Hope this helps.

cheers,

Sanjay
Posted by: AVenugopal

Re: Steam turbine inlet nozzle - 03/29/10 10:47 PM

Thanks a lot Mr Sanjay,

Your advise cetainly is quite helpful.

Best regards

Venugopal