Originally Posted By: Brian Silowash This post was automatically imported from our archived forum.
I saw this mentioned in the Natural Gas Lines thread, and I wanted some more opinions…
I do not see anything wrong with using Teflon tape on NG piping (as opposed to pipe dope). Teflon is a perfectly acceptable sealant in this application, as far as I know. I have seen different types of tape for sale though, for instance at Home Depot. The explanation I got there was that the blue tape was for gas, and the yellow tape was for potable water (maybe it was vice versa -- it may even have been another customer offering the explanation). It was some time ago, but I seem to recall reading the labels, and the only difference I could see was that the thicknesses were different. This doesn't seem to make sense to me, since all you would have to do would be to put another wrap around the joint.
I have seen Teflon tape specified on high pressure industrial gas lines, with no ill effects. What have you heard, and what may I be missing?
Originally Posted By: arosenbaum This post was automatically imported from our archived forum.
Yep…
White is for water and yellow is for gas...
The only difference (I think) is that yellow is thicker tape...
If needed, I'm sure a "bad" plumber/heating guy could use white tape and just tape the pipe like crazy, because... IMO... its just a couple MIL thicker...
Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
There is a difference. It has to do with thickness. Some jurisdictions allow no teflon tape on gas lines. Period.
Substances such as "leak lock" oi superior to both tape (of any thickness), or pipe dope. But, our jobs, IMHO, is to spot defficiencies. I dont look at every gas fitting to determine if tape or dope was used. I look for leaks wherever possible.
-- Joe Farsetta
Illigitimi Non Carborundum
"Dont let the bastards grind you down..."
Originally Posted By: kluce This post was automatically imported from our archived forum.
Teflon tape is not recommend for gas pipes because the cutting oil will eat away at the tape. This is refering to the white tap. I have read this at different places over the years. Pipe dope shouldn’t be used on water because it may wash part of it away into the water you drink. I read this somewhere many years ago.
I have seen both used on water and gas on residental houses and never seen a problem.
Question, why would the thickness of the teflon tape affect the performance of the connection. I was taught to wrap three times, counter clockwise, and two threads away from the edge of the pipe. If using thicker teflon, wrap two times. Just wondering?
Originally Posted By: arosenbaum This post was automatically imported from our archived forum.
When I wrap a fitting, I wrap the fitting the way something would thread onto it (easy way to remember). If you do it the other way, and you thread on to something, the tape will just unwind. I just tape it a few times…maybe 3… maybe 10… whatever looks nice Haven’t had a leak yet… but I would NEVER use teflon (white tape) for gas…
Originally Posted By: dleavitt This post was automatically imported from our archived forum.
As you know there are several types of thread sealant. Color is not necessarily for one or the other. And cutting oil does not have to do with anything, for galvanized water pipe is cut using the same oil.
Just read the usage label on the product and most all will tell why one is better than the other. IE gases, pressure, solvents etc.,
Actually as an inspector we should not even be concerned about what is used or not as long as it does not leak.
Haven’t had a leak yet… but I would NEVER use teflon (white tape) for gas…