Union Operation Failing

Hi - I’m trying to boolean a bunch of pipe object together and I’m having trouble figuring out why my boolean union is failing. Could someone possibly shed a light on what might be going wrong? I’ve attached the file below. Thanks!

oklahomaDrilling_Model.3dm (8.8 MB)

is that the file after you tried boolean operations? many surfaces are double at the same location, you may want to clean that up first. after that you have to assure that all surfaces also intersect with each other properly, thats a bit of a tricky thing to do here with so many surfaces but has to be done for them all to connect.

what do you need that union for?