I would avoid cast. I'm not certain about yard and service lines, but cast iron distribution & main lines have to be inspected regularly. Also coupons from the cast must be removed periodically and tested for wall structure integrity. If possible, perhaps the pressure can be increased at the regulator, CSST run using the existing cast as a casing and another reg at the home to reduce to house pressures. We have also used PE as an insert piping in older steel lines by increasing the pressures to accomodate for the smaller diameter. Is PE not an option for you? It is compatible with LPG, NG and very installer friendly. Whatever chosen might require some coordination with the gas supplier and your installer. I am suprized that Cu is allowed in Nebraska. Our gas comes from part of the same network feeding Omaha and Cu fuel gas piping is only permitted for LPG. I wouldn't use cast, period- even if it costs 1/10 what the other choices do. Soil subsidance and other conditions can lead to failures.
Don't confuse me with facts, my mind is already made up.
Black Iron vs CSST
I for got to mention that this nat gas piping is to be installed inthe basement, conditioned space (not underground).
While I am inclined to use Black Iron as this has been used for 100+ years,
I am curious about the construction of CSST.
Does anyone have info on the "Cross-section" of a CSST.
(Similar to a car radial tire cross-section that shows the rubber, steel treads, etc.)
For CSST, what layer in the cross section (rubber or steel) seals the gas?
The reason I pose this question is when you look at plumbing "stainless steel" hose that goes from the floor to the toilet, although the outside is stainless steel, it is the RUBBER inside that carries the water and prevents the leak. All the stainless steel does is if and when THERE IS A LEAK, it contains water so it sprays a bit but not a catastrophic spray of water.
So going back to gas, even a minor leak is a BIG no no.
CSST CROSS SECTION
[Edited by mechanicalmaster on 02-19-2006 at 12:09 AM]
case for CSST
I recently toured the plant where they mfr. Trac Pipe and I'm certified to use both Gastite and Trac pipe. I find they are much superior to black iron and copper. Follow the mfrs. training and you should be fine.
FYI, Trac pipe starts off as a sheet of 304 stainless steel off a spool and is rolled into a conduit and seam welded. It is then clinched to form the corrugations. Once they have a spool of about 6500 feet, they cap the ends, pressurize it to 125 psi and dunk it into a tank of water to check for leaks. Only once it passes the leak test does it get the outer plastic jacket and inkjet markings.
CN, I think you are confusing the contruction of this pipe with hydraulic or pneumatic hoses. This stuff will survive a 16d nail through a wall at it. The 1/2" has the bending radius of a soft Philly pretzel.
With one fitting on each end, you can fish it through a house like a garden hose and not worry about leaks in inaccessible places. It installs in a fraction of the time black iron does. Around here, it usually prices about the same as black iron installed.
One piece of advice: regardless of what pipe you use, go with one size larger than the tables call for.
Keep the fire inside the fireplace.