Steel
- Threaded Connections
Threaded pipe ends are tapered so they tighten as you turn them deeper. Seal the threads with
Teflon tape
or
pipe joint compound.
Start fittings by hand to avoid cross-threading.
Always use pipe wrenches in pairs, one to resist the torque of the other. Start by tightening the first wrench until it grips the pipe firmly in its jaws. Place the second, 'holding' wrench on the fitting facing the opposite direction. Turn the first wrench towards its open side to engage the pipe.
Measure rigid threaded pipe carefully. It's called rigid for good reason; it won't flex and you can't cut it a little shorter if you measure wrong the first time. Figure that a half inch at either end of a pipe will go into each fitting.
When you need to run a lot of threaded pipe, like for a new gas line, it's best to cut and thread your own pieces. You can rent cutting and threading tools for a day or have the pieces made for you at a plumbing supply shop.
Buy a variety of short pieces of pipe, called nipples, in different lengths. Having choices as you work may save many trips to the store.
Rental Tools
Tools for Threading pipe