In addition to meeting Code requirements, it's also necessary that the end reaction forces be within reason. If your straight pipe has end reactions that are within equipment limits (or within sensible structural design limits) then you don't need the loop. If you're not sure what equipment limits are, check with your equipment engineers. If you're in doubt about "structural design limits," talk to your project's structural engineer.

So the brief answer to your question is that nobody on this forum can give you an answer as to whether the loop is required or not. It's unlikely that, even if you posted the end reaction forces (and moments) we could give you that answer either. The answer lies within your project team.