flexmen,

I am not in the expert level here and this issue is very common to the newcomers. I am giving my opinion here and believe me most of these experts here knows more than these. The way you explained I can say the pipe is hot having a 3" growth. Whether you put a vertical restraint at the bottom or not, since the pipe is hot and you put +Y on top the pipe will rise at a magnitude equivalent to a specific system restriction. +Y means pipe can go up as much as it could but cannot go down. Taking the +Y there in your analysis won't yield an overstressing at all. It simply means to me that a +Y or simply a vertical support at that point does not do any functin to a pipe. Say in reality, the pipe hangs up from your vertical support (a structural beam for example). Depending on how your pipe is supported below, I tried 5 years ago restraining the point which was +Y (same point as what you have mentioned) with a +Y with gap say 1/8" and also 1/8" on the lateral direction (kind of simulating a clamp type support installed loosely). When I run it there was an overstresing in elbows and so the best thing is to replace the +Y with a spring hanger. The lift off you were talking about is taken care of the spring and also will relieve loads below. If it happens that restraing the same point does not yield any reds on your output then its good enough. So far this is part of what I've learned.

Ed_Lamigo