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Electrical conduit pipe 2

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WARose

Structural
Mar 17, 2011
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I was looking at this product on Lowes web site:


From the info given, I have no clue as to the wall thickness or the material grade used (as the specs mean nothing to me). Lowes (of course) couldn't help. Can anyone tell me the info I need from this? Thanks.

EDIT: To save you a look....it says (as far as specs go):
Type EMT
UNSPSC 39131700

Have no clue what that means.
 
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I have only one thing to say, we stopped using metallic pipes for cables long ago, especially inside walls it is not permitted.

All is VP tubing now a days.

/A



“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
WARose - EMT stands for "Electrical Metallic Tubing".
Our other poster beat me to the keyboard on sizing. Imperial measurements (inch): Wall thickness 0.057 (ID 1.049, OD 1.163) for nominal "1 inch" pipe.
Tubing is typically mild steel (0.05 to 0.25% carbon, by weight ... think AISI 1018, for example) with galvanized coating to prevent surface corrosion. My best guess is that the original sheet is cold-rolled, with subsequent forming and welding to create the final "tube".

One manufacturer's link is :
Converting energy to motion for more than half a century
 
It is supposed to conform to ANSI C80.3 whatever protection that offers.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
An important property of EMT is that the inside needs to be smooth (no jagged weld seam or rough plating) so that the wire can be fished without damage.
 
There used to be a rule in the Canadian code to the intent that;
EMT shall be manufactured in diameters that make threading with standard pipe threading tools impracticable.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
It seems I am so old that now a days they only use flex VP hose (pipes), [lol] it is used for recessed mounting in walls.

image_whukl8.png


Can only find one in Swedish, there are different systems but it is standard in sizes etc.


And one in Norwegian.


/A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Waross, I have seen what you describe. The wall thickness is less than standard pipe so it can only be threaded with thread forming dies and not the more standard thread cutting dies.
 
I never heard of threading EMT. It wouldn't fit the knockouts and locknuts if you did, and likely violates listing. EMT is put together with set screw or compression style fittings.
Tugboat,
Please explain the difference.
 
A thread forming die makes a thread by plastically deforming the metal. A thread cutting die removes metal to make the thread. If the wall is thin, the thread cutting die will cut through the wall.
 
We have metal conduit pipes here in very old houses, but we must have stopped using them at least before the 60s.

The plastic ones you could bend with a bending feather and they where easy to cut and assemble.
Now whit the flexible ones that isn't needed any more.
You still would have to take care of taking any sharp edge of the same as a metal one though, you could damage the cables if unlucky.

I am mostly surprised that US and as it seems Canada still uses metal conduit pipes for new build of houses, industrial and large non housing complexes have other types of cable runways depending on other things.

I can't really find anything that would make metal ones better then using "plastic" ones.

VP flexible is easier and faster to assemble.
They can't burn with a open flame of course that can not happen with a metal one either.
VP:s do not need to be earthed.
They can't lead current.
You can't hammer a nail trough them because they are not fixed so they just moves a way.
The same goes for most screws to.
They are surely cheaper then metal ones.
They do not rust.

So all in all whit the price and installation cost and everything else why us anything else. [ponder]

Best Regards A




“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
Steven said:
I never heard of threading EMT. It wouldn't fit the knockouts and locknuts if you did, and likely violates listing.
I agree completely. Neither the ID nor the OD matches standard pipe sizes.
I doubt that EMT could be upset-threaded in a size that would take standard locknuts. It sounds like a lot of wasted time and money to render the EMT unfit for use with quick, cheap and easy set screw fittings.
Redsnake: Conduit is not used in small residential construction. NMD-9, Non-Metalic-Dry, cable is used for small residential.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Well we are not allowed to use Non-Metalic-Dry (none metal shielded cables) inside walls.
I am counting on you correcting me if I am wrong. ;-)
When I am looking for NMD-9 on the net I only find shoes?! [lol]
If the cables are put outside of the wall they are always metal shielded too, not for earthing but because they need to be stiff enough to not hang down between the cable clamps.
Non metallic shielded cables are only used for appliances and then they need to be dubble insolated.

/A


“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
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