Corrosion Protection on threaded GRC

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wadd01

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What are most people using on cut threads of GRC?
NEC 300.6 (A) says you have to reappy corrosion protection - but what is cheep and available?
 
No-ALOX is usually what I use but don't ask me about the listing. I believe that the only product listed for the purpose is a copper based anti-seize compound.
 
Zinc-It spray:

514PPD5C0DL._SL500_AA280_.gif
 
Crouse Hinds makes a good "lube in the tube" with the consistency of vaseline. Below is my favorite in saltwater/extreme environment -

Koprkote10002.jpg

Kopr Shield!​
 
Why are you guys using anti-sieze lube on RMC, when what the code calls for is corrosion protection of the couple threads exposed outside the fitting?
 
A Former employer of mine used to spray Cold Galvy spray in the lid if the can. We then took a small brush and applied it to the exposed threads; it was real classy, quality work.


Never heard of No-lox used for ridgid


JJ
 
JJWalecka said:
A Former employer of mine used to spray Cold Galvy spray in the lid if the can. We then took a small brush and applied it to the exposed threads; it was real classy, quality work.
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If a graffiti artist can make a good looking huge Malcom X mural with spray cans, I have to believe that we can get a good looking job on conduit threads without resorting to little paint brushes. :rolleyes:
 
mdshunk said:
If a graffiti artist can make a good looking huge Malcom X mural with spray cans, I have to believe that we can get a good looking job on conduit threads without resorting to little paint brushes. :rolleyes:
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If you are painting Malcom X murals on the conduit threads I'll call you an artist, untill then your just another guy with a spray can. :D
What is amazing to me is how many guys won't even put a piece of paper behind or around what ever they are spraying, and get overspray all over the place.
 
acrwc10 said:
If you are painting Malcom X murals on the conduit threads I'll call you an artist, untill then your just another guy with a spray can. :D
What is amazing to me is how many guys won't even put a piece of paper behind or around what ever they are spraying, and get overspray all over the place.
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Well thats what seperates us from the Tagg Artist or Muralist. And I bet they don't torque the connections of the panels they install - I'll go so far as to bet a number of us don't either....
 
Galvy spray applied with a brush is nice work. It keeps the spray where you need it not all over the place like a five year old.
It was also applied to the direct ends of a cut unistrut in that fashion.


Malcom X comments like that could be taken the wrong way…. Lets keep it proffesional

JJ
 
JJWalecka said:
Malcom X comments like that could be taken the wrong way?. Lets keep it proffesional

JJ
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True - murals can be done by many poeple of many subjects. Most of the better ones here have either an Aztec or contemporay theme. Still think they have little to do with electrical installation though.
 
300.6(A) Ferrous Metal Equipment Ferrous metal raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, metal elbows, couplings, nipples, fittings and support hardware shall be suitably protected against corrosion inside and outside (except threads at joints) by a coating of approved corrosion-resistant material. Where corrosion protection is necessary and the conduit is threaded in the field, the threads shall be coated with an approved electrically conductive , corrosion resistant material.


Lightweight for thread dope –

TOP > EXPLOSION-PROOF CERTIFIED EQUIPMENT > FITTINGS > THREAD LUBRICANTS > 78227461415
78227461415pcds.jpg


Heavy-duty for thread dope-

273X027_PLI.JPG


From the manufacturer:

Kopr-Shield compound is a unique homogenized blend of pure, polished colloidal copper, rust and corrosion inhibitors that simultaneously protects, lubricates and enhances the conductivity of the mating surfaces to which it is applied. Extremely adhesive, Kopr Shield compound flows smoothly into uneven contours and voids, making application easy, protection and lubrication complete and positive. A stable compound, it will not settle-out, thin, thicken, harden or dry out under the most severe environmental conditions.

Kopr-Shield compound has excellent temperature characteristics - brushed on at -50F to 250F (other compounds either turn solid or run like water at these extremes). Even at 1800F Kopr-Shield remains intact for short terms.

Kopr-shield Compound may be used to advantage in all electrical installations. When the environment is hostile to good electrical and mechanical connections.

When working pipeline projects there spec book (E400) tries to tie into the code as much as engineering tech writers can. Per their call out for conduits-

3.3.3

All conduit shall be square cut, reamed inside, and threaded to connect to couplings and fittings. The Contractor shall use thread compound suitable to arctic environment, to obtain a tight joint. The thread compound shall be listed as electrically conductive and shall not affect grounding continuity of the electrical system. Refer to NEC Article 300-(A).


My commentary:
Perhaps we work in different environments, and interpret the verbage from the NEC differently, but this is the standard I am used to. I believe that between the manufacturers representatives, and others who sit on code making panels, that the wording is quite clearly intended to steer a person into just a few options. The above are some options which exceed the callouts for the work that I use it for, but is the standard for the work in our area.
 
Rockyd said:
approved electrically conductive , corrosion resistant material.


My commentary:
Perhaps we work in different environments, and interpret the verbage from the NEC differently, but this is the standard I am used to. I believe that between the manufacturers representatives, and others who sit on code making panels, that the wording is quite clearly intended to steer a person into just a few options. The above are some options which exceed the callouts for the work that I use it for, but is the standard for the work in our area.
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"Approved" is in the eye of the beholder as opposed to listed or designed for the purpose...
 
Too late to change the verbage for the 2011 NEC. Clarification should be solid. Short of a formal interpetation (90.6) cannot give you a qualified answer.


See Charlie's code rule -

Charlie?s Rule of Technical Reading

It doesn?t say what you think it says, nor what you remember it to have said, nor what you were told that it says, and certainly not what you want it to say, and if by chance you are its author, it doesn?t say what you intended it to say. Then what does it say? It says what it says. So if you want to know what it says, stop trying to remember what it says, and don?t ask anyone else. Go back and read it, and pay attention as though you were reading it for the first time.
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Found a funny neatly written artical on the topic by a car mech.
http://www.sw-em.com/anti_corrosive_paste.htm

Also - there has been discussion on this before - most anti-ox products 1.) differ from eachother wildly, and 2) may not be appropriate - i.e. using products of suspended copper paste for say AL connections. Take a peek at the penetrox pages here, and you'll notice there is no mention of use on steel threads - but some are listed and therefore approved for use on AL conduit threads. And some for copper to copper connections only.

I do not know of any product "Listed" for use on steel RMC threads.
 
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