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The world of pipe fittings

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Re: The world of pipe fittings

#161

Post by johnwalkr »

mgarfias wrote: post #138
jkqwzsoo wrote: post #9

In 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…

A small quibble: the tape don’t seal. It’s a lubricant for the threads wedging together to seal. For a REALLY good primer on the subject, read Carrol Smith’s _Nuts, Bolts, Fasteners and Plumbing Handbook_ (aka Screw to Win).

Such a great book. I’m a mechanical/aerospace engineer and it’s astounding how many in my field don’t understand fasteners and tend to oversize them. It’s seen as conservative but it can actually backfire.

Re: The world of pipe fittings

#162

Post by hilbert42 »

dtgriscom wrote: post #151
hilbert42 wrote: post #125

Earlier quoted context omitted.

Ha! I'm no longer a Padawan so, like you, I'm well acquainted with the practice of spreading things around to the point of saturation. It's not only PTFE tape that I spread around in copious quantities, other notables on the list are screwdrivers (of various sizes and types), superglue tubes (they go off with age anyway), propelling pencil leads, keys, USB and computer cables, USB pen drives, computer mice, adhesive…

When I was a kid, my mom's theory on pencil purchasing was that if she bought enough, the house would be so saturated that you could shake a curtain and a pencil would fall out.

Hum... Clearly, I'm not alone. That's at least some comfort.

Re: The world of pipe fittings

#163

Post by iancmceachern »

luxuryballs wrote: post #68

I thought they were paid so much because plumbing is gross and often just a huge pain.

Exactly, I do the simple stuff myself and only call a plumber when it involves crawling around in a spider infested crawl space, working with poop, or similar things I am willing to oay someone to do.

Re: The world of pipe fittings

#164

Post by johnwalkr »

mannykannot wrote: post #35
jkqwzsoo wrote: post #9

In 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…

What do you think of the advice that it is acceptable to use a tapered male thread in a straight female one? My guess is that if you do that, you have at best one turn of the thread helix holding them together and providing a seal (and perhaps you would be trusting in nothing more than the tape jammed between the threads if you used ten turns of it!)

I don’t think it’s acceptable. Maybe works in pinch to get through a weekend but I would always replace it with a proper fitting. Plus if you damage the female threads or o-ring seat, you’ve made a much worse problem for yourself.

Re: The world of pipe fittings

#165

Post by iancmceachern »

swayvil wrote: post #120

Given the choice, I love pex and those compression-bands that you put on with the special pliers. Pex got flex. For drains, pvc of course. Given run-of-the-mill refurbby waterline junk with plain ol copper, I like that brass kind of compression with the little sleeve. Don't trust sharkbite. Am a mediocre sweater. For gas, threaded with that pipe goo works surprisingly well. Haven't fucked it up yet. I wonder if you c…

Agreed on the compression fittings over the sharkbite stuff.

Re: The world of pipe fittings

#166

Post by pengaru »

mgarfias wrote: post #138
jkqwzsoo wrote: post #9

In 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…

A small quibble: the tape don’t seal. It’s a lubricant for the threads wedging together to seal. For a REALLY good primer on the subject, read Carrol Smith’s _Nuts, Bolts, Fasteners and Plumbing Handbook_ (aka Screw to Win).

> For a REALLY good primer on the subject, read Carrol Smith’s _Nuts, Bolts, Fasteners and Plumbing Handbook_ (aka Screw to Win).

+1 for anything by Carrol Smith

Back in my gearhead days Engineer To Win was a near constant fixture next to the toilet.

Re: The world of pipe fittings

#167

Post by NegativeLatency »

blincoln wrote: post #21
TEP_Kim_Il_Sung wrote: post #16

Earlier quoted context omitted.

hemp fiber > PTFE tape

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.

Generally the lead joints described above were only used for waste plumbing where the max pressure is very very much lower than the water supply pressure

Re: The world of pipe fittings

#168

Post by robk »

jkqwzsoo wrote: post #9

In 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…

This is more useful than Teflon tape I find https://www.amazon.co.uk/Loctite-K97870-Henkel-Sealing-Multi...

Re: The world of pipe fittings

#169

Post by couchand »

rsync wrote: post #121
kennend3 wrote: post #108

Earlier quoted context omitted.

As someone who is NOT a pipe fitter but lived with one for many years.. It was odd reading this and I'm glad someone like you responded to correct things. > 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. Again, not a pipe fitter but this just screams "WRONG". If someone needs to use that much force to tighten it up, one can only assume…

"My roommate had a "unlimited BTU" gas fitter license (Canada Class "A") and this for a living and preferred "pipe dope"" I do this kind of thing a lot as we own and maintain our own water plant. My preferred sealant is the yellow PTFE tape that is used for natural gas. It is quite a bit thicker than the white tape, it sticks to threads better and it is easier to work with, in terms of manual dexterity. I never use t…

I've seen people suggest that white tape should only be 1.5-2 but yellow should be 5 or more, do you have thoughts on that? Is there a difference in usage or is it the same overuse pattern on both?

Re: The world of pipe fittings

#170

Post by fuzzfactor »

aidos wrote: post #116
jkqwzsoo wrote: post #9

In 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…

I think there’s cultural difference where the tongue in cheek context has been lost a bit. They probably use neither 10 full wraps, nor an enraged mountain gorilla, but then I’ve seen stranger things in plumbing.

The lowland gorilla comes to mind . . .
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