Pentration through a steal wall

[encoreman]

I need to make a run through a steel wall. It is a 1/2 inch think steel plate. Someone else is going to weld a 2 x-strong pipe through the wall about 8 inches long. I'm wanting to attach conduit to each end of the steel pipe and run conductors through the steel pipe. The other option would be to run conduit through the steel pipe, but then I would have to find a way to provide a seal between the conduit and the steel pipe.

Question 1:
Can I run conductors through the steel pipe?

Question 2:
If I have to run conduit through the steel pipe how should I seal it (the general contractor does not want to use foam)?

Thanks for your help!

Jack

 

[petersonra]

Question 1:
Can I run conductors through the steel pipe?

I see no reason why you could not. There may be some practical issues.

Question 2:
If I have to run conduit through the steel pipe how should I seal it (the general contractor does not want to use foam)?

I think your best bet is running threads through the wall. or some kind of threaded fitting. maybe even back weld it to the wall. might need special permission to do this.

 

[encoreman]

Pentration through a steal wall

Thanks Bob,

Yes the pipe (welded in by other) will be threaded. I can thread my conduit directly to this steel pipe to provide a very good seal. I was just concerned because the steel pipe is not UL listed.

Jack

 

[petersonra]

Thanks Bob,

Yes the pipe (welded in by other) will be threaded. I can thread my conduit directly to this steel pipe to provide a very good seal. I was just concerned because the steel pipe is not UL listed.

Jack

I would think it would be fairly straightforward to get special permission for such a thing.

Have you considered a bulkhead style conduit fitting?

 

[don_resqcapt19]

I would not expect the inspector to give you special permission to do that. The code requires the use of listed conduit and does not permit it to be welded.
What would the seal have to keep in or out?

 

[renosteinke]

Talk to the guys who do commercial kitchen hoods!

Their supplier - usually a specialty plumbing house - has nice compression fittings that are designed to let conduit pass right through them. They look like ordinary EMT compression fittings, but have a slightly larger ID.

Now ... for attaching to the steel wall: 1/2" plate is plenty thick to thread, or weld to. If you've got access to a welder - and there's probably a welding contractor on site already - have him punch a hole and weld a 'socket' to the wall. The 'socket' is like a coupling, except it is flat on one end (for welding) and threaded on the other to take pipe threads. So, you would use a 1" socket to mount the pass-through fitting, that would let a 3/4" pipe pass through the wall.

 

[iwire]

I need to make a run through a steel wall. It is a 1/2 inch think steel plate. Someone else is going to weld a 2 x-strong pipe through the wall about 8 inches long. I'm wanting to attach conduit to each end of the steel pipe and run conductors through the steel pipe. The other option would be to run conduit through the steel pipe, but then I would have to find a way to provide a seal between the conduit and the steel pipe.

Question 1:
Can I run conductors through the steel pipe?

Question 2:
If I have to run conduit through the steel pipe how should I seal it (the general contractor does not want to use foam)?

Thanks for your help!

Jack

In my opinion the NEC rules out 1

As far as 2 depending on what you are sealing out I would use link seals http://www.linkseal.com/ but the sleeve they weld in will need to be sized to fit the link seal.

 

[infinity]

I need to make a run through a steel wall. It is a 1/2 inch think steel plate. Someone else is going to weld a 2 x-strong pipe through the wall about 8 inches long. I'm wanting to attach conduit to each end of the steel pipe and run conductors through the steel pipe. The other option would be to run conduit through the steel pipe, but then I would have to find a way to provide a seal between the conduit and the steel pipe.


Jack

What kind of seal are you looking for, watertight, fire-stop or some other type?

 

[encoreman]

When I get to the site, there will be a 2 inch 2x strong pipe about 6 inches long welded into a hole in the 1/2 inch plate. The pipe will be threaded on each end. One side of the plate is outside a building, the other side is inside a building.

I was hoping to put an LB on each end of this pipe. I now understand I must run conduit through the pipe and attach the LB to the conduit.

Now I have space between the pipe and the conduit that needs to be sealed.

I looked at http://www.linkseal.com/ and that is a possibility provided I can find one that will fit.

I may just use silicon caulk between the conduit and the pipe and call it good.

Thanks for the input!

Jack