Re: Teflon Tape

[Wright Huntley <jwwiii at pacbell_net>]

> Date: Fri, 08 Aug 2003 08:24:51 -0700
> From: "Sherlock Wong" <s_wong at aristoslogic.com>
> Subject: Teflon Tape
>
> A plumber at Home Depot told me that teflon tapes does not seal the
> joint. When a coupling is tightened, it generates heat, which makes it
> harder
> to tighten fully. The teflon provides lubrication, allowing the coupling
> to be
> tightened fully.

And it is impossible to wet, so water cannot get past it if it just fills 
most of the space between the threads. It is fairly worthless for gas 
lines, and has a tendency to shred and clog needle valves or other 
downstream devices with such small apertures. Use a paste thread goop for 
gases.

When I worked at HP Labs, the company had issued an edict that no teflon 
tape was to be used on *any* plumbing except water lines. It had caused no 
end of problems with lab gear. [Downright dangerous problems, in some cases.]

> Normally, with plumbing, overtightening is bad. But I think that CO2 is
> different,
> by tightening the coupling, you are compressing the washer into the
> groove on
> the tank valve. To compress the washer takes alot of force on the
> wrench.

Amen!

> The beer supply place where I get my CO2 refilled said to put all my
> weight
> on the wrench to tighten the nut.

Soap tests will confirm that this is often needed.

Wright

--
Wright Huntley -- 760 872-3995 -- Rt. 001 Box K36, Bishop CA 93514