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Posted By: Trumpy US Plumbing fittings? - 01/02/04 08:47 PM
Could anyone tell me what sort of fittings are used in the US for plastic and copper water pipes on the supply side of the system.
(ie:before the plumbing appliances)
Is PTFE thread tape used over in the US?.
Is Hemp and Graphite used on Brass threaded couplings?.
Just wondering. [Linked Image]
Posted By: iwire Re: US Plumbing fittings? - 01/02/04 09:21 PM
Yes we use PTFE thread tape or a paste type compound.

As for Hemp, some definitely use it, but I do not think the same kind you are talking about. [Linked Image]
Posted By: Trumpy Re: US Plumbing fittings? - 01/02/04 10:52 PM
Thanks Bob. [Linked Image]
Yes the type I was referring to is Plumbers Hemp, apparently you'd have to smoke a few acres of it to get any high out of it!. [Linked Image]
Posted By: pauluk Re: US Plumbing fittings? - 01/06/04 11:13 AM
Trumpy,
Things I like about typical U.S. plumbing over British:
  • High-pressure hot and cold water at all appliances, no cold storage tank in the attic.
  • Much better drainage systems, without the horrible open discharge arrangement which is still common here.
  • The toilet design with its much higher water level in the bowl.



[This message has been edited by pauluk (edited 01-06-2004).]
Posted By: John Steinke Re: US Plumbing fittings? - 01/18/04 06:37 PM
Common practice here is to apply PTFE tape to male threads, with a PTFE-containing paste on the female threads. Steam and gas lines have different practices.
Copper lines are typically brazed (soldered), with a lead free (or silver) solder. Threads, where they occur, are taped & pasted.
Hemp I have only seen as a seal (covered with solder) on cast iron drain pipes, and as a valve packing.
Plastic is generally glued. Where plastic transitions to something else, the plastic fitting has the male threads.
There was a massive failure afew years ago with a crimp-fitted plastic tubing system; there is a new version out now, but I'm still very skeptical.
Our toilets drain out the bottom, to a line in/below the floor. The joint is sealed with a waxy ring (6"OD, 1" thick, appx.). This differs fron the Euro-style of the toilet having a relatively small pipe exiting the back, which connects to the sewer line with a 3-lipped rubber coupling.
Posted By: pauluk Re: US Plumbing fittings? - 01/20/04 10:35 AM
Quote
Our toilets drain out the bottom, to a line in/below the floor. The joint is sealed with a waxy ring (6"OD, 1" thick, appx.). This differs fron the Euro-style of the toilet having a relatively small pipe exiting the back, which connects to the sewer line with a 3-lipped rubber coupling.

British toilets come in both rear and floor-exit versions. The rubber coupling is practically universal now, but in older installations the joint was often made with the hemp that Trumpy mentioned.

The other main difference is that our traps are of a height which results in only a very low level of water in the bowl compared to U.S. designs. It makes it harder to keep the bowl clean, but I suppose it has the advantage of solving the dog problem! [Linked Image]

By the way, British toilet cisterns have a different arrangement too, with an up-&-over siphon in place of the simple flapper valve.
Posted By: Trumpy Re: US Plumbing fittings? - 01/23/04 09:21 AM
John,
Thanks for the info, mate.
Is that Silver solder that you are talking of, like the Silphos that we use here to weld Copper Refrigeration pipes?.
Quote
There was a massive failure afew years ago with a crimp-fitted plastic tubing system; there is a new version out now, but I'm still very skeptical.
I would be too John, you wouldn't believe how many houses over here, had thier ceilings collapse due to what was known as a Compression coupling system for PE piping, ultimately made for the DIY plumber, but you'd expect better quality in fittings than that!.

Paul,
Over here, the traditional Cold Water Cistern in the roof is slowly being replaced by the Ajax (Pressure-Reducing) Valve.
These are OK, as long as they are installed correctly and have a relatively stone-free supply.
But, If I could count all the times that I have been sent to a new house because there is no Hot Water and to find the Ajax valve blowing water (through the H/W overflow) onto the roof!. [Linked Image]
BTW Paul, back siphonage is prevented here by having the overflow on the toilet cistern lower than the bottom of the ballcock valve and a tube leading down from the outlet of the ballcock valve.
Posted By: pauluk Re: US Plumbing fittings? - 01/23/04 12:35 PM
Both toilet cisterns and the attic storage cisterns here were often fitted with a "silencer tube" in the past -- A straight tube running down from the ball-valve outlet to discharge the supply below the water level.

The water bye-laws banned them some years ago due to the possibility of back-siphonage, but there must be many still in use.
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