1) when is galvanized pipe used for gas lines...? my supply line looks like galvanized but one of the branches looks like black iron ....and how much pressure is in a natural gas line ..?

Some places it can be used anywhere, others require it outdoors, and still others do not allow it at all. So it just depends on where you are located.

There was a time when some jurisdictions did not allow galvanized because of the possibility of the zinc coating flaking off inside the pipe, and clogging orifices and valves. Most places do allow it now. Figure the drip legs take care of problems. Here it is required for pipe exposed to the weather, but prohibited undergroun. Some areas still allow black outside but require it to be painted.

In very rough terms, the pressure inside a residence is about 1/2 PSI.

Thanks for your replies .... if the line isn't underground or exposed to the weather is black iron pipe prefered...? and how long should the drip leg be for 1\2" pipe ..?

3" long

The only reason for "preferring" black pipe is usually because it is cheaper. And the pressure for natural gas is just over 1/4 psi. Propane is about 1/2 psi.

I have never seen a dripleg with anything in them. Except during "bungalow bustin" The foreman wouldn't order out the 50 pound boxes of rags for the gas guys to wipe the pipe down with. So, they wouldn't swab the oil out of the ends of the pipe. They always left a 1" drop with a 1x1/2x1/2 tee. A couple of times, when I went to pipe out the water heater and furnace, I would remove the nipple from the bottom of the tee, and about a 1/2 ounce of oil would be in the cap.


Peace out,

Kordts

"The only reason for "preferring" black pipe is usually because it is cheaper. And the pressure for natural gas is just over 1/4 psi. Propane is about 1/2 psi."


Ok...thanks....at the local supply house it seemed that galvanized and iron were exactly the same price....I'll go with the galvanized....

if you are using it indoors, there is no advantage to using galvanized for gas.
the supply house is either overcharging for black or undercharging for galvanized.

The reason for Black Iron Pipe rather than Galv. is; Galvanized Pipe will flake and the flakes can plug your appliance burner. It is my understanding that Gas Piping Codes require the use of Black Iron Pipe.

rudythplbr45 wrote:

"The reason for Black Iron Pipe rather than Galv. is; Galvanized Pipe will flake and the flakes can plug your appliance burner. It is my understanding that Gas Piping Codes require the use of Black Iron Pipe."

I have never run down a definitive answer on this issue, but a few comments:

I have heard three different reasons why black pipe should be used instead of galvanized:
1. galvanized pipe produces flakes that jam gas orifices.
2. black pipe is cheaper
3. using different pipe for gas makes sure gas pipe won't be used for water lines.

theory 1 is the most common, but according to quite a few internet sources it is false.

theory 2 is true but it is not significantly cheaper if one looks at the overall cost of the project.

theory 3 is from my dad and I have never heard it anyplace else.

As a practical observation using black pipe outside, especially near the ocean, seems like a really bad idea since it corrodes very quickly.

Apparently, codes vary from location to location on the issue, but I am not sure which of the various internet pontificaters on this issue are correct. Some codes seem to require galvanized pipe for gas and some seem to preclude it. The sign at Lowes yesterday said that galvanized pipe shouldn't be used for gas lines.

So what exactly is the code situation with regard to iron pipe for gas and are there any valid technical reasons why not to use galvanized for gas?

Not correct the IFGC in both the 2006 and 2012 Editions allow galvanized pipe to be used for natural gas.

In the commentary of the International Fuel Gas Code (IFGC-2012) under Section 403.4.2 for steel and wrought-iron pipe it states:

"Steel pipe must be Schedule 40 or heavier, must comply with one of the listed standards and can be black iron or galvanized. Contrary to popular belief, natural gas does not adversely react with the zinc coating on galvanized pipe".

Identical language is also used in the 2006 Edition in the Code and Commentary of the IFGC.

For Gas Pipe its better to use Black pipe but never use cut threaded pipe for piping connection as it is not safe. I have got this information from PCFSCT webiste that Cut threaded Pipes are now replaced with Rolled threading technology which is safe and Green as well as PCFSC give gurantee for no leakage no Rolled threaded Pipe nipples and good they are also good for enviorment.

Rolled threaded Pipe nipples is safe because of following reasons

-Perfect Mating Between Male & Female Thread Increases the tightness between the threaded Pipe and fitting and hence no leakeage on Rolled threaded Pipe Nipple.

- 100% perfect thread teeth as Rolled thread is manufacture by rolling process so from the 1st Pipe Nipples till the manufacturing of last pipe nipples the profile of the pipe nipples and thread remains the same but if you see the cut thread they are manufacture by cut knife tool which det weak after sometime and hence not perfect threading.


- Excellent Rust-Resistance on Rolled Thread Pipe
Original hot-dip zinc coating of the galvanized pipe remains intact, and is not cut away as with lathe cut ones.

-The density of the rolled thread pipe is increased greatly and makes, at least, the “same thickness” as the original pipe itself, and forms an anti-oxidization layer of high metallic density against rusty.

- Pipe Material Not Cut Away Makes Thread Mechanical Connection Much Better

The mechanical properties of the pipe thread are greatly improved as no material is cut away and the weight per unit length of rolled thread pipe remains unchanged, and further more the metal density is increased.

It is also enviorment friendly becuase No metal waste scraps is from rolling thread, material saving; Production environment is clear and friendly;

INSTALLATION ON SITE IS More Safe;
Easy & convenient for tightening;
50% - 70% saving of sealant and tapes;
A trial test of piping system 100% successful pass in 1st time;
No re-call work;
Over 50% efficiency up in installation;
Daily maintenance on thread connection of piping system zero



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