Hi,

I am currently unsure whether to "turn on" the Bourdon Effect when calculating valve forces. I have a valve in-between very long straight sections of buried pipe (i.e. 2 to 3 times the virtual anchor length). However, I find that when I turn on Bourdon effects, there is a significant increase (up to 40%) on the axial forces acting on the valve.

My questions are:

i) Why does the Bourdon Effect make such a large difference (even on straight lengths?) - I am aware that Bourdon effect is the rotation of a non-circular cross section under pressure.
ii) Is this an accurate representation of the "real" forces acting on the valve?
iii) I've seen a lot of discussion relating to the use of Bourdon effect, i.e. Bourdon effects are necessary whenever pressure displacements are "significant", Is this true for straight pipelines too?

Thanks,

Jaidev