UL/AGA Listed Teflon Tape

[littletoes]

Is there any information listing as to why Yellow teflon tape is UL/AGA (American Gas Association), listed for use on gas pipe, and as to why "white" teflon tape is not?

What we've been finding, the unlisted "white" tape shreds easier, and clogs gas regulators, to the point of non-operation.

Any help would be appreciated.

 

[MikeHalloran]

You seem to have answered your own question...



Mike Halloran
Pembroke Pines, FL, USA

 

[littletoes]

I imagine it is due to improper application, or "over" application, if you will.

Hence the quote;

"Over-use, or mis-application of thread tape may be a hazard. An excess amount of tape can prevent mating threads from fully engaging, therefore reducing the shear point of the threads. The use of teflon tape in addition to a pipe dope compound can also be dangerous, because it can become too much between the flanks of the threads. As the tape material is so soft, excess or overhangs may easily break off and form a foreign body contaminant that could jam a valve seat etc.

Thread sealing tape is almost entirely applied by hand, owing to the ad hoc nature of most repair work, although at least one machine is available for production wrapping of fittings"

 

[moltenmetal]

Why the yellow and not the white?

From observation, it appears that nobody is permitted to produce the yellow tape expanded to a specific gravity less than about 1.0 to 1.3, whereas you can get the white or pink sh*t to specific gravities ranging from 1.3 down as low as 0.25.

We don't do AGA regulated work, and we exclusively use tape with an s.g. no lower than 1.0. The denser tape stays together better and is better at large void filling.

Application is key. And in cycling operations, tape alone is insufficient. We always top-dress tape with an anaerobic thread sealant paste, unless the paste is not compatible. In services where tape debris is not permitted, we forego the tape entirely and rely on the paste alone.

 

[littletoes]

We have observed all of the problems listed in the quote on my reply at one time or another.

We DO NOT use Teflon (PTFE) tape under any circumstances. Pipe paste has been used for years without Teflon, if they could do it then, we can do it now. It looks unprofessional, and almost every person uses more than is required.

Three wraps, on the first four threads, without pipe "dope", if you must. Both/either were designed to be used independently of each other, yet a "trend" has started in the Trades with the "need" to use both. We run as much pipe as anyone, and yet we get along fine, without the use of Teflon tape, or without any large amount of pipe "dope".

The "Tighter" tolerance that Yellow Teflon tape is held too, is what helps prevent so many of the problems found with White.

Clogged gas regulators being the for-most problem. To the point of non-regulated gas escaping either through the vent, and/or excess pressure experienced downstream.

Either property damage or injured personnel being the outcome.

If pipe joints where Teflon is used are 3 to 5 times weaker, or more likely to fail at high pressures (in excess of 1000 psi), why take the chance?