On Tue, 05 Mar 2013 12:26:45 -0600, dpb wrote:

On 3/5/2013 10:18 AM, Jim Wilkins wrote:
"Joe wrote in message
...
In article
,
Pilgrim
wrote:

Can any one tell me what the difference between rigid conduit and
iron pipe? ....
...

Is either better for structural uses?
...

Neither is specifically intended although a lot is used for railings,
etc., etc., etc., ...

Have to judge by comparative wall thickness and intended use/loading,
etc. As noted earlier, GRC is slightly lighter than Sch 40 pipe of the
same nominal dimension so will be somewhat less strong based solely on
that difference in resultant bending moments, etc.

Rigid has an appearance benefit of generally a smoother surface but
that's purely aesthetics, not functional.
For something like a railing where form is more important than
function - in that you want something big enough to fall well to hand
- so 2 or 2 1/4", the strength of iron pipe is way more than necessary
- so the advantage of smooth, slightly less strong rigid conduit makes
it the "better" material for that job. Lots lf other places where the
small difference in strength is a non-issue, as the size used for
aesthetic or other reasons, is overkill even for the weaker material.