plugging an iron gas pipe

[adder1969]

Ok, at the risk of sounding incompetent, I'll ask the group for their input :-)

I've removed a gas fire and need to get rid of the valve/regulator that's sticking up fromt he floor. The floor is concrete/screed and the gas pipe runs in the screed. There's a T in the presumable iron gas pipe which then goes on to feed the cooker in the kitchen. I want to remove the fittings and cap off the tee with a plug but I need it not to protude any higher than the tee itself. Does such a recessed type plug end exist? I knwo I can look for myself but does anyone have any idea on whether the fitting needed is likely to be regular compression type thread or tapered? (I'm planning on using a threaded seal not a compression one and it won't be very accessible)

[diy-newby]

I don't think you should be messing with gas pipes unless you are Corgi registered.

[Si]

In message , diy-newby writes

it's Ok, as long as you are 'competent'

[adder1969]

..and aren't charging someone money for it. So, with that cleared up and my competence aside....

[jgh]

Are you saying the T is buried in the concrete, with the middle poking up to feed the gas fire: fire

------|---------- ======*=====>cooker

I'd (get a plumber to) cut out enough concrete to cut out the T and replace with a short section of pipe with straight couplers. You can get couplers that will slide along a pipe, as you won't have any slack on the pipe buried in the concrete.

-- JGH

[John Rumm]

Have a look at BES part number 6446 on

(I'm planning on using a threaded

Assuming the pipe is a iron type with a female threaded tee on it, then a suitable plug and some gas PTFE tape should do it. Carry out a gas soundness check before[1] and after fitting.

[1] saves lots of frustration looking for a leak in your new work when in fact it already existed somewhere else before you started!

[Ed Sirett]

This subject has been done to death. Please read the Gas Fitting FAQ. The OP should use a 1/4 BSP plug. The Tee fitting maybe a long way down. You must know how to use a gas gauge to test for leakage before and after the job. If you don't then leave it to a pro.

[adder1969]

Yes the T is buried in the screed, so that the top of the T is just level with the top of the screed. I looked at the hollow plugs (on BES as someone suggested) but they still appear to protude up higher than the T itself.

I can chip away the screed to reveal the T and pipe and the only way I can see of using a coupler is to solder it. Using threaded fittings I can't see how it could work.

I read the gas fitting FAQ but it doesn't address my particular question.

[diy-newby]

Don't mess with Gas, leave it to someone who knows what they are doing.

[John Rumm]

If it is an iron pipe then threaded fittings are the only acceptable option. What is more since the pipe is in concrete you wont be able to do anything with the tee itself since you wont be able to rotate the pipes to tighten or loosen anything. So you really have two options - fit a double ended threaded nipple to the tee and then a blanking cap. That will sit 1/2" to 3/4" above the tee, or use a blanking plug. These normally have a small protrusion on them to allow you to tighten them with a spanner - but should not sit more than 1/4" above the tee. You may be able to get it to sit deeper in the thread is you cut a small amount off the bottom of the threaded section.

[John Rumm]

You have said this twice now. If he has read the FAQ then there is a fair chance he does know what he is doing - at least within the scope of the small amount you need know to take on this particular job.

[jgh]

I don't know if you can get them for soft iron gas pipes, but you can for electrical conduit. You cut out the T and a inch or so of pipe on either side. You ream each end of the pipe with more thread than you need, enough thread to completely thread on a coupler: ---------

---/\/\/\/\/

---/\/\/\/\/ ---------

Pop the reamed short section in between and reverse thread the couplers back onto the joining pipe: ----------

---/\/\/\/\/ \/\/\/\------

---/\/\/\/\/ \/\/\/\------ ----------

-- JGH

[Ed Sirett]

If you are going to hack the concrete out that much then you will probably be able to turn the tee enough to put a plug in the end.

You then need to get a satisfactory test, corrosion proof the pipe and make good in that order.

It depends on what flooring you are going to have but if it's carpet then

5mm of protruding plug may not be a problem.

[David Hansen]

On Tue, 4 Dec 2007 01:53:30 -0800 (PST) someone who may be adder1969 wrote this:-

Soldering something onto an iron pipe/fitting buried in concrete would be an interesting task, even if the concrete is chipped away.

Unless you wish to get into an increasingly complex job involving several fittings then the sensible approach would seem to be to plug the fitting, taking the precautions mentioned in this thread. How neat this looks depends on the floor finish, which you have not explained in detail.