Floating ring design

[senaratne]

Hi all,

Can some one suggest good reference for designing floating rings. I have an application where operating temperature is 480 C and have to use 316 SS for the 850 mm NB pipe. This pipe section has a metallic bellows which develop a pressure thrust which I have to contain with in the small pipe section. What I am trying to do is to use carbon steel rings on either side of the bellows and set of tie rods to contain the pressure thrust. The problem I face is due to difference in liner thermal expansion between carbon steel and stainless steel, and carbon steel ring temperature is lower than Stainless steel pipe, if I weld the ring directly to pipe, pipe will choke and develop stress crack in the future. So I have to use floating ring with lugs welded on the pipe to tranmit the pressure thrust from pipe to floating ring and then to tie rods. In this design enough gap is kept between pipe and the ring for pipe to expand freely. Can enyone suggets some literature, pare for which cover this type of design??

Thank you
Jag

 

[vesselguy]

If I interprete you correctly, you need to provide tie-rods assembly to hold back the expansion bellow located between two S.S. pipes during expansion. Is that right?

If so, then wouldn't the typical TEMA expansion bellow design fit in here?

Conceptually, can you not weld a C.S. flange to the C.S. bellow and weld S.S. flanges to the S.S. pipes and bolt these together for pressure joint. Then mount a loose S.S. tie-rod holder ring behind the pipe flange for the tie-rods.