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[email protected] etpm@whidbey.com is offline
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Default Replacement sight glass

On Fri, 29 Apr 2016 22:46:24 -0400, wrote:

On Fri, 29 Apr 2016 19:34:51 -0700,
wrote:

On Fri, 29 Apr 2016 20:44:34 -0400,
wrote:

On Fri, 29 Apr 2016 12:26:20 -0700,
wrote:

On Fri, 29 Apr 2016 13:28:12 -0400, Ed Huntress
wrote:

On Fri, 29 Apr 2016 09:55:07 -0700,
wrote:

On Fri, 29 Apr 2016 07:23:55 +0100, David Billington
wrote:

On 28/04/16 22:00, Bob Engelhardt wrote:
On 4/28/2016 11:22 AM, Ed Huntress wrote:
And jeez, Iggy, teach someone how to do a proper job with Teflon tape.
... g

Since we're giving Iggy thread advice, let me add this: I sometimes
have a taped joint leak. I never have a leak on a joint where I've
used "paste" sealant. With PTFE or Teflon.

Bob
I've seen plenty of paste sealant joints leak whether done by myself or
professional gas fitters on various pressure systems including low
37mBar systems. They should always be checked.
Of course they should be checked, that's how I knew every joint I made
with teflon tape on that crappy black iron pipe leaked, and how I knew
none leaked when I remade them with the paste. Only a fool would
assemble a joint that's supposed to be leak free and not test it.

Eric

How many layers did you put on? As the size of the pipe increases, you
need more layers. With 1-inch pipe, I use three layers.
3 layers. The guy at the store selling the pipe said that would do it.
I asked because the threads were so ****ty. They were very sharp and
torn, like they were cut with a dull die set. I think the sharpness
just cut through the tape. Whatever the reason the goop is all I have
used since and I have had zero leaks since. With brass and bronze and
stainless fittings I have never had problems using tape, but the black
iron pipe sold around here for gas service sucks. The threads always
look like crap.
Eric
With brass and bronze they often seal perfectly with nothing.

As they should. The tape makes for easier assembly and disassembly.
Especially the disassembly.
Eric

They don't call them "dry-fit" or "dry seal" threads for nothing.
Using teflon tape on these threads virtually always compromises the
seal, whether it makes them easier to take apart or not I don't know -
but it generally DOES make it necessary.

If a fitting is a dryseal (NPTF) then I would use no sealant. But most
fittings are not NPTF. At least most of the ones I see and buy. YMMV.
Eric