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PE gas pipe with pin hole

PE gas pipe with pin hole

PE gas pipe with pin hole

(OP)
Fellow engineers,
A 2" PE pipe (SDR11) carrying natural gas, operating at 50psi develops a pin-hole leak. I would like to install an electrofusion saddle on it but supply cannot be interrupted. Other than installing a by-pass and performing a squeeze-off, are there any other methods to seal the hole temporarily (long enough to install the saddle)? Thx.
austsa

RE: PE gas pipe with pin hole

Well, start with the statement "supply cannot be interrupted"...

All it would take is one carelessly tossed match, no?

RE: PE gas pipe with pin hole

There are several bolt-on mechanical saddle connections qualified for use with HDPE pipelines as well.

RE: PE gas pipe with pin hole

Put a screw in it - if there is enough metal available. Might want to use brass - less chance of a spark.

RE: PE gas pipe with pin hole

If you put a screw in it you may wish to consider an O ring under the head. I have used this technique on water service. Mechanical saddle could be covered by the code whereas the odd "Tek Screw" may not be.

There are wrapparound springs used on steel pipelines but with PE the creep characteristics may be a problem as the pipe will continue to reduce in diameter under load.

What is wrong with the EF saddle? Are you concerned that the temperature may cause ignition?

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

RE: PE gas pipe with pin hole

(OP)
stanier,
Yes, I do not want to EF with gas leaking. Thus, I'm looking for a quick way to temporarily stop the leak, then I'll EF the saddle on.
austsa

RE: PE gas pipe with pin hole

I would have thought that you could shroud the EF joint with a box and flow through an inert gas (N2) and then perform the EF joint. There would not be an explosive mixture. Otherwise if it is a pin hole leak then perhaps a hot soldering iron would enable you to smear the PE over the hole.

PE is one of those dreadful materials where adhesives dont stick. On the other hand molten PE sticks to evrything.

You could hot tap either side of the leak with a valved saddle. Complete a bypass loop then squeeze of the leak.

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

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