High pressure Steam

This same question was posted on www.eng-tips.com so I've taken the liberty of copying the following two answers, I think they are very relevant]

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pennpiper (Mechanical) 15 Jan 07 14:47

JacobsTim (and others)

BigInch made the following statement:
"The stress engineer is usually responsible for locating supports, "

This statement is both true and not true. I believe it is true for "BigInch" because that was the way he was trained, the way his company operates and was what (all, most or some) the projects required that he has worked on. It is true and consistant with his experience. There is nothing wrong with this manner of operation. I would furthur recomment that you look at all of his responses, the ones to this question and other question as being very good advice.

However, his statement is not true and consistant with the training, experience, manner of operation and project types for all pipers and all companies. I am not speaking for all pipers but it was not true for me, my experiences and my company. Where I "grew-up" as a piper, I (and hundreds of others like me over the years) recieved training in the fundamentals of proper pipe routing and total system design. This included many classroom hours in the basics of stress, flexibility, forces, weight, support, expansion, etc.. This was classroom instruction conducted by the head of the stress department.
Why was this training done? Very simple! The ratio of piping designers to stress engineers was (and probably still is) 25:1. So this means there was a work load issue to be considered. Also, the head of the stress department and the manager of the total piping department did not want bad or unworkable designs submitted to the stress department. This would only increase the workload because of the recycle. We were required to submit what we considered a workable design. And we needed to be able to defend it. In this enviroment the piping designer located all the support points and the stress engineer checked the total line or system for complience to the codes and other factors as required by the project criteria.

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NozzleTwister (Mechanical) 15 Jan 07 19:35

I give you a star pennpiper. My sentiments exactly.

Back to JacobsTim's original question, I can speak for a Stress Engineer who has had this exact same problem.

I have the following comments and suggestions.
1) Adding a dummy leg would be my last choice. Try to add or relocate steel as required to avoid the dummy. If the dummy can't be avoided, moving or adding a support can reduce the force the dummy is required to support.
2) Sh is less than 1/2 Sc at 510 deg. C.
3) 1 meter is a very long dummy leg at this temp.
4) The Moment (force times length) is the problem with the local stresses.
5) If no other options, shorten the dummy as much as poosible.
6) Consider a heavier schedule elbow at the dummy attachment and taper bore elbow ends to match pipe.
7) If the pipe and dummy are large, consider inserting a plug of insulation inside the dummy against the pipe and insulate a portion of the dummy leg.

Since your Stress Engineer has already said your situation won't work, I hope you are working to give him some options that will.
NozzleTwister