Help with Aluminum ridged conduit .

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Minuteman

Minuteman

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I was given a chance to bid replacing a Power Frequency drive and part of the job includes replacing 3 sections of 3/4" Aluminum ridged conduit (each with back-to-back 90? bends).

I have worked with a lot of ridged conduit over the years, but never with Aluminum. The stuff is readily available at a local parts house, but I am seeking some input about working with it.

Any tricks to threading it? Can I use a regular pipe die? What about bending it? Can I use my Klein 1" EMT bender? Any suggestions would be appreciated.

Thanks!
 
The first thing that I remember about bending Aluminum conduit is really funny. I marked the conduit for the proper stub measurement. Then I put my bender on the mark and proceeded to make my ninety degree bend. Usually when I start my bend with rigid steel conduit, I give the bender a sharp hard jerk to start the bend. Well, I almost went over on my rear end since the aluminum conduit was so easy to bend, it came right up much quicker than I ever imagined; the bend was made with hardly any effort.

For a few threads, you should be allright. However after a few cut and threads, the aluminum seems to clog things. Also clogs the teeth and saws and grinders.

Also aluminum is more difficult to fish with a metallic fish tape. Seems like there is more drag .
 
If you have worked with steel RMC then aluminum should be a breeze. Using the next size up EMT bender (1" for 3/4" conduit) will make bending easier and more uniform then using a hickey. 3/4" AL bends very easily. As thunder said be careful of binding when threading. Make sure you use the proper threading oil.
 
Use Nolox or Penatrox on the threads while assembling.
This will help with screwing the pieces together.

Tim
 
Be careful with your bends as it is not as forgiving as rigid. If you over bend it and try to take some out like you can do with rigid, you can't. It won't let you take bend out, it just bends at another point on the pipe.
Don
 
Thanks all!

This is for an urgent repair at a Gov't installation, and they gave us 24 hours to submit a bid. Which we did. So, we should find out soon if we are going to do it.

Your input has been most helpful.
 
tkb said:
Use Nolox or Penatrox on the threads while assembling.
This will help with screwing the pieces together.

Tim
Click to expand...

Wire Termination Compound is designed for that use only, I would recommend the product as "anti-corrosion paste-type compound" such as KOPR-Shield? (a registered trademark of Jet Lube), a conductive anti-corrosion surface compound suitable for application on field-cut conduit threads where protection from corrosion is necessary. (Courtesy of Thomas & Betts)
 
Joe,
That (KOPR-Shield) is a copper based product and I don't believe that it is suitable for use with aluminum conduit or conductors. The instructions on Pentrox A say "for use as an anti-seizing thread lubricant".
Don
 
Ul Dvyw

Ul Dvyw

don_resqcapt19 said:
Joe,
That (KOPR-Shield) is a copper based product and I don't believe that it is suitable for use with aluminum conduit or conductors. The instructions on Pentrox A say "for use as an anti-seizing thread lubricant".
Don
Click to expand...

Thanks Don, I was thinking about this from the UL directory:

CONDUCTOR TERMINATION COMPOUNDS (DVYW)​

Conductor termination compounds are for use on splice and termination
connections of aluminum, copper-clad aluminum and copper conductors
where used to retard oxidation at the conductor/connector interface.

These compounds do not have a deleterious effect on the conductor metal, insulation or equipment when used in accordance with the manufacturer?s installation instructions.

Reference should be made to the product label located on the smallest
unit container for specific instructions as to the proper use of the compound.

For additional information, see Electrical Equipment for Use in Ordinary
Locations (AALZ).

The Listing Mark of Underwriters Laboratories Inc. on the product is the
only method provided by UL to identify products manufactured under its
Listing and Follow-Up Service. The Listing Mark for these products
includes the name and/or symbol of Underwriters Laboratories Inc. (as
illustrated in the Introduction of this Directory) together with the word
??LISTED??, a control number and the following product name: ??Conductor
Termination Compound??.​
 
As far as aluminium threading goes, the best thing I have found is to use kerosene. I used it a lot when I was chaseing threads in a machine shop. And I still use it now. A guy I work with couldn't believe how much better the threads turned out.
 
Just because it may not be listed doesn't mean that it is not suitable for the purpose.

I was taught 30 years ago to use Penatrox on aluminum threads and don't know of a single instance that this has caused a problem.

I know it works. If it ain't broke don't fix it. :-D
 
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