Tap 1" pipe?

adambnyc

I have a long run to a rad that gets downsized to 1" in the basement before traveling to the second floor. I'd like to drill and tap a 1/2" hole in the pipe and install a BnJ vent.

Is it ok to tap a 1/2" hole in a 1" pipe? Where should I make the hole? Top of pipe, side?

Fred

What are you attempting to accomplish by doing this? Is this a one pipe system? That 1" pipe has minimal air in it. The radiator vent (or trap, if 2 pipe) can handle that. What is the size of the radiator it feeds? If the radiator EDR is greater than than 1" pipe can accommodate, venting it isn't going to change that. A 1" pipe can supply a radiator up to about 25 EDR, on a one pipe system, a bit more on a two pipe). If your radiator is much larger than that, you need to put a larger pipe in. In any case, you don't want a BNJ vent for that pipe. It will provide no value and serve no purpose over a regular radiator vent.

Hap_Hazzard

Absolutely not. Think about it. The wall thickness of a schedule 40 1" pipe is .133". The thread pitch of a 1/2" NPT male thread is 0.07142857". So how many threads can you cut into that hole you want to drill? Almost 2 if you do everything right. Think that's going to work? Even if it doesn't leak, the male fitting will block about half of the transverse area of the pipe.

adambnyc

Thanks!

ChrisJ

If you want to vent a pipe, I would drill a fitting such as an elbow and tap it. 1/8" will give you up to a Gorton D vent which is the same as a Gorton #1 main vent. Plenty of venting for almost any 1" or 1 1/4" runout.

adambnyc

Thanks Chris. I'm gonna leave this one up to the pros. Tapping a century old elbow myself just makes me all sorts of nervous. Need that "been there done that" person.

New England SteamWorks

I thought of you today Adam. A long time ago someone tapped a tee for a 1/2" vent. It was in the wrong place and no longer operative so I went to remove it and cap. Simple, right? Of course not! The nipple in the tapping snapped right off. Too small for a sawzall, so delicate hand surgery:



Painstaking, but all good in the end:



Moral: Not a good idea to tap pipe or fittings.

adambnyc

What a PIA. I abandoned this quest on the direction from the team here. The pipe in question is connected to a single rad in the baby room. I'm getting an adjustable rad vent and will mess around from there. Thanks for the follow up!

Steamhead

We tap rather frequently to install vents, but there is a practical limit depending on what you're drilling into. In a pipe, no more than 1/8" since the wall thickness won't support threading in larger sizes. A cast-iron fitting has thicker walls and we tap these up to 1/2" with no problems.

One thing that helps a lot is to tap rather shallowly, so the pipe or vent doesn't screw in far enough to block the pipe. Most times we're tapping right at the end of the main so a slight obstruction has no effect.

And use plenty of Teflon, so if the pipe or vent must be removed, it'll come right out.

JohnNY

Steamhead said:

And use plenty of Teflon, so if the pipe or vent must be removed, it'll come right out.

@Steamhead, do you have a preference for teflon tape, or paste? I'm still using wick and dope quite a bit, but I often wonder if I'm just stuck in my father's world with that. My guys love this new Blue Monster tape or whatever it's called.

Steamhead

Both.

ChrisJ

3-4 wraps of blue monster and smear on a thin layer of Megaloc over the tightly wrapped tape with your finger. The PTFE tape seals better and the dope lubricates better.

Perfect seal every time.

For some reason, I kind of like the smell of Megaloc cooking on a new steam pipe. Maybe that's a bad sign.

Sailah

pipe sniffer

Hap_Hazzard

If it's thread tape, it's not Teflon™.
https://www.chemours.com/Teflon_Industrial/en_US/teflon_tape.html

ChrisJ

Hap_Hazzard said:

If it's thread tape, it's not Teflon™.
https://www.chemours.com/Teflon_Industrial/en_US/teflon_tape.html

Teflon is Dupont's brand name of PTFE.
So PTFE tape can be called Teflon. It's just like Freon is a brand name, and actually doesn't cover Suva (R134A) or Puron (R410A) but people still call them Freon.

Hap_Hazzard

Correct, except that DuPont is no longer the trademark holder. Last year they spun off their performance chemicals division as a new company, Chemours ("chemical" + "Nemours"?), which now holds the trademark and patent for Teflon™.

What Chemours is doing is trying to keep their trademark from becoming a generic synonym for polytetrafluoroethylene before it goes the way of kleenex, xerox and scotch tape. This allows them to bring suit against companies who claim their products contain Teflon when they actually contain polytetrafluoroethylene made by a competitor. Ultimately, it's probably a losing battle—just ask Kimberly-Clark, Xerox and 3M—but I respect their position.

BobC

I think we need to find a nice tall cliff so we have some place to store all the lawyers. All the money spent on this should be used for better products, not for the business equivalent of political correctness.

Bob

Canucker

Hap_Hazzard said:

Correct, except that DuPont is no longer the trademark holder. Last year they spun off their performance chemicals division as a new company, Chemours ("chemical" + "Nemours"?), which now holds the trademark and patent for Teflon™.

What Chemours is doing is trying to keep their trademark from becoming a generic synonym for polytetrafluoroethylene before it goes the way of kleenex, xerox and scotch tape. This allows them to bring suit against companies who claim their products contain Teflon when they actually contain polytetrafluoroethylene made by a competitor. Ultimately, it's probably a losing battle—just ask Kimberly-Clark, Xerox and 3M—but I respect their position.

Southwire takes a similar position regarding the Romex© brand

neilc

BobC said:

I think we need to find a nice tall cliff so we have some place to store all the lawyers. All the money spent on this should be used for better products, not for the business equivalent of political correctness.

Bob

bottom or top ?

BobC

Insert at the top and wait.

Bob

Sailah

Would anyone like to comment on this?

Fred

Aside from the one that looks like it leaks? It should work. Looks like 1/4" tapping, which is fine for Gorton #1's and #2's

Danny Scully

My only comment @Sailah is, why aren't they big mouths?

Sailah

I was told it's 1/8" NPT tappings into pipes.

I won't explain how the picture came to me but it was concerning our vents. My thought is why spend the money on venting if you are going to do it this way? Why not break the pipe somewhere and install a proper fitting so that you can take advantage of the money you are spending on venting.

I guess I would ask it simply.

Would any of you pros ever do a job like this unless specifically instructed to by a client to getter done?

Abracadabra

1/8" pipe will vent 2.5 cfm @ 3oz.
gorton #2 will vent 2.2 cfm @ 3 oz.
So by the numbers it'll work. I don't like it tho. A good accidental hit to one of those vents and you've got steam leaking all over the place. I'd never do it that way, but maybe they couldn't find a proper spot to add a tee?

JUGHNE

These are 1/4" tapped into 2". I wanted the strainers and distance from the main. It would have been quite a weight on a 1/4" tapping without the mini-clamp supports.

JUGHNE

If I had to open the 2" run for any reason it would have gotten a tee installed. I am a one man shop with limited pipe threading tools, so breaking a 2" line open is not a simple job for me.
This was the most economical solution for the home owner who previously had no venting at all.

Would a 1/4" tap be enough for a Big Mouth?

Sailah

Abracadabra said:

1/8" pipe will vent 2.5 cfm @ 3oz.
gorton #2 will vent 2.2 cfm @ 3 oz.
So by the numbers it'll work. I don't like it tho. A good accidental hit to one of those vents and you've got steam leaking all over the place. I'd never do it that way, but maybe they couldn't find a proper spot to add a tee?

From what i was told this is fairly common work and they anticipate doing a lot more just like this. In other words, they are doing it this way because it's the fastest way to get it done.

I was asked to spec a substantial qty of my vents up against the competition, but I don't see how I could make it work with their insistence on using 1/8" tappings. And I could never recommend going in there with a 3/4" tap.

with the amount of vents they are talking, it would save them a ton by just doing it right and reducing the amount of vents they are using and piping it in properly. I don't expect to be able to convince them so I'll probably just politely say I'm not interested.

Danny Scully

Of course we would @Sailah , it's a commonly used technique. And to answer your question as to why we don't cut out a portion of the piping, thread in place presumable, and add a fitting...well, because we don't have to In all honestly, every situation is different. But really there is nothing wrong with tapping/threading a pipe.

Sailah

JUGHNE said:

If I had to open the 2" run for any reason it would have gotten a tee installed. I am a one man shop with limited pipe threading tools, so breaking a 2" line open is not a simple job for me.
This was the most economical solution for the home owner who previously had no venting at all.

Would a 1/4" tap be enough for a Big Mouth?

I understand that. For a single job, you do the best you can with what you have. But this is a large scale venting change out in a large city with apparently a crew. If your job detail was to change or add 1000s of vents to steam systems all over, would you not invest in proper piping tools? I have to think that this was just one building, but others may have proper places to add vents and their MO is to leave the 7/16" drill in one drill and the 1/8" tap in the other. Bam bam done next.

In your situation I think that's a fine job and you obviously took pride to do a workmanlike job.

The picture I posted was sent to me as an example of their work. Personally it looks lazy and half ****. There I said it, now I feel better. Lol

JUGHNE

Personally, I would not do the 1/8" tap simply because of the small internal diameter. It would not take much to plug that opening.

Sailah

Danny Scully said:

Of course we would @Sailah , it's a commonly used technique. And to answer your question as to why we don't cut out a portion of the piping, thread in place presumable, and add a fitting...well, because we don't have to In all honestly, every situation is different. But really there is nothing wrong with tapping/threading a pipe.

Ok I respect that, maybe I was a bit harsh about judging others work.

I worked in a custom cabinet shop when I was younger. I remember asking my boss,

"Greg, is this good enough?"

"Peter, perfect is good enough, do it over"

Always stuck with me. I don't ever achieve perfection, far from it, but I always strive to.

BobC

i think they are just looking at it from a labor point of view. use the least amount of labor to do the job and pray it holds up.

Bob

JUGHNE

If I had a big boy crew for that job you describe, I would go with the welded saddles and use an antler assembly.
Build it on a bench with a union and strainer for multiple vents.
Less pipe wrench time on a ladder.

Here a tee did get installed....still concerned about weight on fittings; this is in a boys shower room; who knows where they would want to do pull ups.

rick in Alaska

I agree with the saddle idea. Not sure if you can get bolt on saddles that have steam rated gaskets though. We used saddles all the time in fire sprinkler work. Then you can put in what ever size you need, depending on the main pipe size of course.
Rick

Steamhead

I would have tapped 1/2" NPT inste4ad of 1/8" or 1/4". Not that hard to do if you have the right tools.

We've been tapping since before we started the company and have never had a problem. If done right, they don't leak.

New England SteamWorks

2" or smaller, I would never do it. Cut a section of pipe out, stick the 701 on and thread both ends, tee, union, done. Can't be more labor than drilling and tapping multiple holes.

I found this recently:



In this case it was 3", so no 701. Still, it needed far too much venting for tapping, so the 90's were replaced with tees.

LionA29

Nice setup @RI_SteamWorks

EBEBRATT-Ed

@RI_SteamWorks , love the old elbows that's old stuff!!

Sailah

@RI_SteamWorks

From now on if you put that many vents in its required that you polish them! I love that pic.

LionA29

@Sailah -There should be an award for the best "Barnes & Jones Mantle"
@RI_SteamWorks would've been a candidate!!