thermoplastic materials at -150F

[suzanparvez]

Hi, We are manufacturing at present plastic pipe for oil and gas industry. Guys can you suggest me which thermoplastic materials will be good at -150F. We will make pipe from these materials.

Also please suggest about thermoset polymer.
thx a lot.

 

[Ashereng]

Just curious. What is the application in the oil and gas industry that is going down to -150 °F?

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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[suzanparvez]

for alaska

 

[Ashereng]

Your pipeline is above ground? I thought that they would be buried?

Sorry, I can't suggest a material.



"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

 

[Zapster]

Above grade or below grade, you will not find -150 degF temperatures in Alaska. You would be hard pressed to find -75 degF ambient temperatures. Could you be confusing ambient temperatures with wind chill temperature? What product are you designing for that would require -150 degF design temperature?

 

[UWH]

Coldest temperature ever recorded in Alaska was -80F.

http://www.usatoday.com/weather/wcstates.htm

Coldest temperature recorded on Earth was -89.4C (-128.9F) in Antartica.

http://en.wikipedia.org/wiki/Coldest_temperature_achieved_on_earthtarctica.

 

[suzanparvez]

zapster I have been asked to do something with that temperature range. Its a composite pipe product. I think rubbery material may be a choice.

Thx UWH for giving me those links. But they will be transfering CNG and its not only the ambient temperature and so forth and it also has to deal with the product itself.

 

[Ashereng]

suzanparvez,

I think the ambient temperature direction was initiated by your response of "for alaska" to my question of "What is the application in the oil and gas industry that is going down to -150 °F? ".

If you responded initially with trasport of CNG, I think the direction would not have gone in the ambient temperature direction.

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

 

[joeswoes]

If, for some reason not clear, you require ductility in non-metallic piping at -150F, then you should use a material with a glass transition temperature below this value. This is the temperature at which a material transitions from ductile to brittle. At -150F, PTFE is ductile, but you have a brittle problem with metal housings. I am familiar with development work using PTFE pipe, without housings, for low pressure/drainage applications and also using composite lap joint flanges.

 

[pmover]

my opinion only . . .

i would not recommend/be buying plastic pipe for CNG service in alaska, especially if there is no substantial design and in-serivce data to support the use of such pipe. too many design considerations, of which, seismic is a critical factor.

good luck!
-pmover

 

[sterl]

I believe you will probably have best luck looking at a crogenic hose in terms of material performances. Have seen hoses supported at 30" size handling cryogenic temperature fluids. Don't know about the ecomics of this byt some of the properties might be of interest. Try:

http://www.specialtyhose.com/cryogen.htm

There are some looking at semi rigid polymers for very low temp services:

http://www.bpf.co.uk/downloads/files/VicProperties_UK.pdf

Whether that has compatability with the CNG and its minors, I couldn't guess...

There are PTFE-Jacketed HD hoses that will handle high pressure at low temperature, the Cryo people use a flock of them, but the only thing they use in rigid pipe is a high nickel stainless

 

[25362]

From my sources, of the various unfilled fluoroplastics, only PTFE and PFA have brittleness temperatures as low as -200^oC.