Having just completed a small project involving plumbing, this post on my blog comes from the heart.
The world of pipe fittings
51–60 of 270 posts
Re: The world of pipe fittings
#52I've helped out with some plumbing work in an older house, and it's pretty fascinating to see the progression of technologies. 100 years ago, most drain pipes in the US were massive cast-iron pieces with no threads at all. They were mated together, then the joint was filled with a compound called oakum. To really hold it together, the plumber would pour molten lead on top of the oakum. Just taking that stuff apart is…
> I like PEX, but I know opinions vary What’s not to like about PEX?
I'm about to use PEX for the first time on my hydronic heating system, which is only ~20psi and limited volume (autofill valves are an anti-pattern). Maybe I'll fall in love, who knows.
Re: The world of pipe fittings
#53The Teflon tape is only to be used as a friction modifier as NPT and other tapered threads seal on the threads. Reduced friction means that you can get enough load to deform the metal threads and create a seal. Be careful to not add tape to the first 2 threads as small pieces of Teflon tape can break off and get stuck into valves and things within appliances causing them to leak. There is nothing wrong with pipe dope…
Re: The world of pipe fittings
#54Earlier quoted context omitted.
For sure. Those oakum + lead joints were problem-free a century after they were installed. How many of us can expect that from the things we do at work? The only reason some of that pipe needed to be replaced was that it was fused (by rust) to mid-20th-century galvanized pipe that had rusted completely shut.
Those lead joints were leaching lead into the water. If it was a supply pipe, as opposed to a drain, then people were ingesting that lead. It needed to be replaced whether it was leaking or not.
Also, nearly all water supplies (municipal, at least) are pH adjusted to be slightly basic, which causes lead to form lead carbonates and oxides, which is (basically) insoluble in cold water. Still good policy to replace lead supply lines, but not a crisis unless you allow your water quality to fluctuate (ala Flint or a number of other US cities, sadly)
Re: The world of pipe fittings
#55"When buying male fittings, it’s best to always get tapered ones so they fit in either." I tried that with a shop compressed air system and got lot of leaks, hissing, and the compressor turning on frequently. And I never did get the system not to hiss somewhere, so I can sympathize and ditto this rant. Even when using matching fittings, with gobs of tape and/or dope, and enough force to destroy multiple fittings, it…
https://toolguyd.com/quick-guide-to-air-line-couplers-plugs/
Re: The world of pipe fittings
#56Earlier quoted context omitted.
Normally the market is supposed to correct these things but sadly we've created a culture that looks down on physical labour. Now there is a small group that can charge whatever they want.
Is the market not supposed to reflect culture?
Re: The world of pipe fittings
#57Re: The world of pipe fittings
#58In case anyone from the US reads this, BSPP and BSPT fittings are rare and incredibly frustrating here, as our NPT (National Pipe Taper) threads are different and the selection of BSP(P/T) fittings is extremely poor in comparison. Also, I work with NPT fittings quite a lot: > For what it’s worth, I tightly wrap the tape 10 times round the male thread and get an enraged mountain gorilla to tighten it up. This is a WTF…
The standard advice I've been given when it comes to either vacuum or cryo fittings is "cut anything American off it as soon as it arrives and put DIN standard or KF kit on as soon as possible". Standards are a pain and that xkcd about there being too many of them is very, very true.
Re: The world of pipe fittings
#59Re: The world of pipe fittings
#60I've helped out with some plumbing work in an older house, and it's pretty fascinating to see the progression of technologies. 100 years ago, most drain pipes in the US were massive cast-iron pieces with no threads at all. They were mated together, then the joint was filled with a compound called oakum. To really hold it together, the plumber would pour molten lead on top of the oakum. Just taking that stuff apart is…
> To really hold it together, the plumber would pour molten lead on top of the oakum. This is pretty interesting, because plumbers are called 'lead-pourers' (loodgieters) in Dutch, and I had always wondered why.
Same origin in English as well! (Plumbum = Lead)