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Black vs Galvanized Pipe?

I did my gas lines in 1993 , used yellow teflon tape . I had to remove teflon and use pipe dope . I even over titened the pipes and they still leaked , with teflon tape .

Teflon does not protect metal from corrosion , dope does .

I bought green coated underground gas pipe that was powder coated NOT the green taped pipe .

The reason i did my pipes , was my nieghbor got his meter red tagged in the middle of winter !

He had to fix and have the county inspect . I did not want an inspection , so i copied him and avoided the inspector ...

Bimetal corrosion cut all the pipes in the area ! a small current created by dirt and rain over a long period . Change your underground pipes every 8-10 years . It only costs $50 in pipe and a pick and shovel ..

BTW i ruined / extruded 3 blades on a small metal cutting band saw ( Harb-Frt) I changed the angle on the pinch rollers to pull the blade inward , then i noticed the deformation ( extruding) in the blade . It was the push roller . So i changed that angle to oppose the force . It came from China with the roller helping to distort the blade . It was forcing the blade to twist too much , too soon . Still have problems with low power . Motors have a tag says how much heat the motor makes , but not how much H.P. ! Sears and Roebuck , 1969 , First to lie and use input power rather than the "legal" output power ...

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clare wrote:

Reply to
werty
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I haven't had problems with teflon tape on gas lines -- but I used it frequently with exotic gases on high pressure lines, so I was accustomed to working with it under those circumstances.

Sta> I did my gas lines in 1993 , used yellow teflon tape . I had

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Reply to
M Berger

I found that the hard part was getting anyone at the gas company who both knew what they were talking about and was willing to say. I got a whole bunch of vague CYOA from those people, no definitive guidance. I finally called the local building inspector to get the skinny for my area. This can vary a lot too. I've heard that the building inspectors in a nearby metropolitan jurisdiction are jerks whose response is always "hire a contractor who knows", and that jurisdiction has a draconian and expensive tanglefoot maze of permits and licenses. It's a damned club. The local guys have always been very helpful. The "right answers" here were black pipe with dope or copper with flare fittings. Yellow teflon tape is permissible, but its use is discouraged. I don't think I asked about galvanized pipe. Different gas has different amounts of corrosive impurities. I recall that copper was not permitted in some parts of the southern U.S.

Reply to
Don Foreman

The unified color code for service identification is as follows: Yellow for flamable petroleum products - particularly natural gas lines Red for electrical services Blue for potable water supply Purple for "used" water -

Industrial coding is generally yellow for inherently dangerous materials including fuels and toxic materials. Blue is for non hazardous gasses, and green for non hazardous liquids. Red is for fire suppression, including sprinkler water.

Reply to
clare at snyder.on.ca

You read the part about corroding threads , or did you miss it

Teflon does NOT work on iron/steel threads for the quick rusting ...

I got the same "excuse" from a youngster in the Air Farce about how those super sonic , nuke carrying , MACH 7.8 jets use ONLY teflon .

He did not itemise the planes that use iron and steel pipe !!!

As you must guess , Airplanes preceed teflon !!!

Cant learn , wont learn ......

M Berger wrote:

Reply to
werty

How can you tell ?!! Its a government ARBITRARY F#@!!*^^ law , it can't possibly have any sense to it !! In AZ the law says or "said" to use teflon !! IT DONT WORK , but that makes the government happy , it triples the gas inspections , and they hire 3 times more gas inspectors !!

Cant use lead pipe dope , the lead will jump off the pipe and climb into the frig and attack me at breakfast .... Or it will deplete the ozone .... or it will deplete Bushes bank account in the Caymans ,, regularly annoited by Dupont , from R 134a ....

snipped-for-privacy@lycos.com wrote:

Reply to
werty

Reply to
Lloyd E. Sponenburgh

I have used ptfe tape _specifically_ to protect threaded joints from corrosion... Zinc locking rings on Amphenol connectors, screwed to stainless steel platinum resistance thermometer housings all wetted by warm seawater from power station condenser water boxes. It _does_ protect against corrosion if used properly. Pipe dope and ptfe both work if used properly and neither work if abused.

My iron underground gas pipes were changed after 45 years to polyethylene. I don't expect them to need changing again in the next century or two.

Mark Rand RTFM

Reply to
Mark Rand

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