SHR,

You are confused. The effect of presure elongation is primarily on straight pipe. The dominant effect of pressure on an elbow with a slightly oval cross section, is to open it out. Thus the effect of pressure on a piping system might be, that opening of an elbow has a marked effect on, say, a long piece of connected pipe and its end displacement.

Do a little test for yourself with a simple geometry and change the 'Activate Bourdon Effects' settings.