Threading sch 80 pipe

[odj22sailor]

Hi All,

Anyone have any experience with threading NPT using sch 80 pipe?

[UFO8MyCow]

What do you need to know?

[UFO8MyCow]

I am guessing you are just talking about threading your pvc supply or return lines and that should be pretty easy. You will need a pipe thread tool. The local rental place should have them pretty cheap. My local place only wants $8 for four hours for one that will do from 1/2' to 2".

You will slide the open end over your pipe and it will hold it straight then ratchet it in until the pipe is barely sticking out the other end.

[iammrhappy]

What are you goals with the threading?


Why dont you just couple it with a slip/thread fitting?

[odj22sailor]

I was curious if anyone has has any issues threading sch80. Leaking stuff like that and is it common to do this? It seems like a good idea...

[Gorgok]

Its common to thread iron pipe... not pvc. The only time i would consider cutting threads on pvc is for something non-critical oddball things like float switch extension rods.

[laverda]

I have threaded schedule 40 without any problems, so it should no problem. I like being able to make custom pipes with all the extra adaptors. I like the cleaner look and more compact plumbing I can do that way.

[Windy2]

I have threaded schedule 40 without any problems, so it should no problem. I like being able to make custom pipes with all the extra adaptors. I like the cleaner look and more compact plumbing I can do that way.
Do you know what kind of stress or cracking will occur due to the threading? You can buy threaded pvc but in all the cases I have seen, the threads were formed into the pipe and not cut.

[UFO8MyCow]

You should not thread sch 40 PVC it is to thin. It may work but you are taking a big risk.

When sch 80 is threaded the max pressure is halved so for a 1" pipe it will drop from 630 psi down to 315 psi.

I wouldn't worry to much about stress as long as you are using sch 80 we are running almost no pressure in our systems

[laverda]

I have never had a problem with cracking. As UFO states there is almost no pressure in our systems. If you plumbing is under stress, then you need to redo it properly. If your concerned about cracking don't thread it. Another thing you can do is buy longer then needed pre threaded pipe, cut to the length you need. Then you can clue one end and have a threaded fitting on the other end.

[laverda]

Duplicate

[odj22sailor]

I thank you all for chiming in on this tread...I went ahead and threaded all of my connections to my Unions. I did use cement at all turns. I had a couple of drips but nothing big. Thanks all for confirming i am not crazy....

[UFO8MyCow]

so you threaded and used cement? if so may I ask why?

[Gsxkid]

Anyone that thinks this is a good idea is crazy lol. They make slip by thread adapters that one can glue on. You guys are taking something simple and making it harder. Not only that but they make sch 80 nipples in different sizes.

[skeeter_ca]

Maybe he already had the unions?

[1234]

so you threaded and used cement? if so may I ask why?

+1

too much work, epically if your going to use cement anyway - more things to leak