Joe:
When I was first learning we used alot of conduit rigid of course and EMT was very new and not recomended at least not by our Boss. Generally to answer your question depending on the pipe size a 24-36 inch 'Rdgid' pipe wrench,and on 3inch pipe a chain wrench, our shop rule was to take down until it smokes. To be perfectly honest if those existed years ago I was never aware of them and our company never bought them, I was with the same company for 25 years before I started my own business, but that was always wrench tite.
So when I saw that I just Assumed it was an EMT coupling.
