Iron compression coupling. Will it hold?

[pls2000]

A question for someone with more experience with these things than I have

https://www.homedepot.com/p/Mueller...tern-Compression-Coupling-160-004HC/100155616

If this joins pipes that are essentially free on both ends, neither pulled out of the coupling nor pushed into it, and holding the normal 60-70 psi city water pressure, will the pipes be blown out?

I need a way to join temporarily two pieces of 3/4 steel pipe, one of which is old enough that trying to break open a fitting would be like trying to win the lottery.

++PLS

 

[James Henry]

They are reliable. Clean the ends of the pipes, Put pipe dope on the threads for lubrication.

 

[Sponsor]

 

[hj]

IF the pipes are "smooth" it may blow out.

 

[pls2000]

>Put pipe dope on the threads for lubrication.

Why? The threads aren't a sealing surface. If I want lubrication I'd put a little silicone grease on them.

 

[James Henry]

Because plumbers usually have a lot more pipe dope with them than grease. We save that for rubber seals and faucets. I never put grease on a threaded coupling. Call me crazy.