Gas PTFE tape vs.water PTFE tape

[mike004]

Is there any difference between gas PTFE tap and normal water plumbing PTFE tape? They look identical, to the naked eye. Is it OK to use water PTFE for gas, or vice versa?

Mike

 

[Mushybees]

Gas PTFE tape is much thicker. Can be used on joints on water pipe work but it's overkill IMO.
Regular PTFE shouldn't be used on gas joints but you shouldn't be working on gas pipes if you don't know that.
Don't mean to be a smart arse as i'm not qualified to work on gas either. Just thought i'd point out the obvious before someone else rips you a new one.

 

[namsag]

Personnal prefrence is one wrap gas ptfe for everything as it is so much easier to use

 

[wiggikins]

Depends How Dexterous you are!!

 

[namsag]

would give my right arm to be ambi-dexterous the old ones are the best

 

[wiggikins]

Very Droll!

 

[Softus]

Regular PTFE shouldn't be used on gas joints

I don't see why not.

but you shouldn't be working on gas pipes if you don't know that.

So is it your belief that everyone who made a gas joint before PTFE tape was introduced was incompetent?

 

[Onetap]

Is there any difference between using gas PTFE taps and more turns of standard PTFE?

 

[namsag]

normal ptfe is different from gas ptfe and something in the gas reacts with it and causes it to leak so gas grade ptfe should be used it has a slighty different make up so it does not react same as paste and ptfe should not be used together on gas as this also causes a reaction

 

[baxpoti]

normal ptfe is different from gas ptfe

You got something to back this up with?

 

[Agile]

Regular PTFE shouldn't be used on gas joints

I don't see why not.

Of course you would not see why because you are not trained to work on gas!

but you shouldn't be working on gas pipes if you don't know that.

So is it your belief that everyone who made a gas joint before PTFE tape was introduced was incompetent?

PTFE is only one method of making an acceptable gas tight joint. The acceptable jointing pastes are another and have been available for nearly 100 years.

Gas PTFE is a lot thicker than standard PTFE ( although I dont think its any different chemically ) and that makes it very good for many water joints and in particular for the parallel threads on hot water cylinders which seem to present a considerable difficulty for many plumbers.

Tony

 

[Onetap]

Gas PTFE is a lot thicker than standard PTFE ( although I dont think its any different chemically ) Tony

The relevant standard seems to be BS EN 751-3:1997.

This says it is to be;

" Thread sealing tape manufactured from virgin unsintered PTFE, without fillers or additives."

and ;

"......two classes of PTFE, mainly differing in thickness and mass per unit area, suitable for fine (F) and coarse (G) threads."

So it seems the material is the same, it is just the thickness that differs.

Is there any difference between using gas PTFE taps and more turns of standard PTFE?

So anyone know? What's the CORGI answer?

I think I might have answered my own question, G grade tape should be used on coarse BSP threads.

Which raises a different question, why is the thin stuff sold for plumbing?

I once asked a gas fitter in a plumbers' merchants why PTFE wasn't used on gas joints (this was before the gas tape became available).

He said; " It will EXPLODE!"

 

[Softus]

Is there any difference between using gas PTFE taps and more turns of standard PTFE?

So anyone know? What's the CORGI answer?

CORGI is not any kind of authority on materials and fittings used for gas work.

Which raises a different question, why is the thin stuff sold for plumbing?

Because it's incredibly useful, and because gas PTFE is often too thick.

I once asked a gas fitter in a plumbers' merchants why PTFE wasn't used on gas joints (this was before the gas tape became available).

He said; " It will EXPLODE!"

He was talking about his own head.

 

[Onetap]

Is there any difference between using gas PTFE taps and more turns of standard PTFE?

So anyone know? What's the CORGI answer?

CORGI is not any kind of authority on materials and fittings used for gas work.

There must be a standard text book answer, which you CORGI chaps/Keepers of the Sacred Wisdom will all know?

I don't have the British Standards listed on the Screwfix PTFE.

Which raises a different question, why is the thin stuff sold for plumbing?

Because it's incredibly useful, and because gas PTFE is often too thick.

But it shouldn't be used on coarse threads. The only fine threads you see in plumbing are on some compression fittings and they don't form the seal, so you wouldn't use PTFE on the thread.

He said; " It will EXPLODE!"

He was talking about his own head.

I nearly exploded with laughter; he was deadly serious.

 

[Softus]

There must be a standard text book answer

There are standards.

I don't have the British Standards listed on the Screwfix PTFE.

How's about EN331:1998, and BS 746:2005, and BS 1552:1995?

Which raises a different question, why is the thin stuff sold for plumbing?

Because it's incredibly useful, and because gas PTFE is often too thick.

But it shouldn't be used on coarse threads.

I don't see why not.

The only fine threads you see in plumbing are on some compression fittings and they don't form the seal, so you wouldn't use PTFE on the thread.

I agree, and at no point did I imply otherwise.