Posted on 08/25/2024 10:12:24 PM PDT by Paul R.
Sometimes one runs into the problem of pipe or hose connectors made of different types of metals needing to be threaded together. This can happen when replacing plumbing in an older home, or, for that matter with garden hoses and fixtures.
There are of course various anti-seize products on the market, and I've used Permatex 80078 to good effect on occasion, but, I rather question if it should be used in potable water situations, or even for hoses out to the ol' garden. Oatey "Great Blue" Pipe Joint Compound or Harvey "TFE Paste" work well as pipe joint compounds, but are not to my knowledge rated for use with, say, brass to other metals threaded connections (to use the garden hose example.) Or, maybe they are???
Or two hose ends are welded together. (One was brass, one was "something bright silver".)
Would Oatey "Great Blue" Pipe Joint Compound or Harvey "TFE Paste" prevent this? Again, this is more than just a matter of, say, iron-to-iron getting stuck together - here we have dissimilar metals corrosion at work.
Bah!
Anybody know / have experience with this?
Of note, Apparently Oatey owns Harvey, but the two products ingredients lists are significantly different... Also, the Oatey product is blue, is rated for PET, and costs less per oz.
I used to like Harvey and Oatey’s music back in the 70s and 80s . . .
If the connection has a washer or gasket then that will seal the water from the connecting threads. So long as the tape or sealant compound doesn’t extend past the washer or gasket you are good. I’ve use good old Teflon tape and had good results.
Look for sealants used in food processing.
https://www.saftlok.com/stl/TPS-FD_Pipe_Sealant.htm
https://www.plus-co.com/products/plusco214-thread-compounds-food-grade-sealant.html
MOLYKOTE 112.
Yeah, thing is, even trying to be careful, sometimes I see a little of the anti-seize compound get “inside”. But put on too little and the dissimilar metals do their thing...
Tape works but wears out quickly if the connections are pulled apart (unthreaded and then reconnected) even as little as 2 or 3 times.
Good links, but, really, I was wondering about the Oatey and Harvey products as I already have almost 16 oz. left of the Oatey “Great Blue”, and almost 8 oz. of the Harvey “TFE paste”.
Great stuff, but I’m not seeing it rated as safe in potable water systems?
The Teflon tape works well. I’ve also cut the ends off the hoses and replaced them with plastic hose repair parts. That has become my go to fix that garden hose problem.
It is a thinner version of MOLYKOTE 111 which is listed as useable in potable water situations. MOLYKOTE 111 would serve your purpose just as well. A light recoat would be advisable for every reassembly.
Anybody?
What’s the best stuff to use on black iron pipe for gas lines?
BECAUSE LIGHT BULB BASES are no longer brass and are now aluminum-—I have found that I have to use SPRAY DRY Silicone on the bulb base, before I replace a burned out bulb.
The fixtures are also aluminum...
Had a bulb weld itself to the fixture. Had to shut down the house power to get it all taken apart.
Started using the spray silicone after that-— NO MORE Problems.
For wheel lugs & lug nuts, I use ANTI SEIZE, which is a ‘paste’ with a brush attached to the cap. NOT expensive-—keep it in the car along with other spares.
ANYWHERE I have to assemble nuts & bolts that might have to be DIS-ASSEMBLED—even corral clamps, I use Anti Seize.
Some of the best I’ve used for home and industrial piping systems. Our go-to in industry was RectorSeal number 9. For home systems T plus 2 and no. 5.
https://rectorseal.com/brands
https://rectorseal.com/rectorseal-t-plus-2-group/
https://rectorseal.com/rectorseal-no-5-group/
Put Teflon tape on everything. Tighten until it stops leaking.
Teflon tape then Teflon paste.
Really? I lose sleep at night just hoping I have water in the morning, here in Arizona.
Will the dissimilar metals ever touch? Of course, that’s what threads do.
Will water be present anywhere where the two dissimilar metals touch, permitting ionic exchange? Of course.
Put plastic sleeves/fittings between the parts or go all one metal.
Can’t do it cheaply.
Yellow Teflon tape for natural gas.
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