×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

piping of hydrogen production unit?
2

piping of hydrogen production unit?

piping of hydrogen production unit?

(OP)
In the power plant we use hydrogen to cool generator.
after producing of H2 in electrolyzer,compressing to 130 bar,removing water and O2, we fill the capsules with H2(99% purity).
one of the pipe in the filling station that connect to capsule have been faild and have leakage of H2 and must be replaced. this pipe is Cu alloy and is flexible and coil state to facilitate of connceting to capsule.
how can I find or select the best cu alloy for this purpese?

pl help me.

 

RE: piping of hydrogen production unit?

I am not sure I understand the question, but: We have used ordinary 1/4" copper tubing (and Swageloc fittings) with 1800 psi hydrogen for years.

RE: piping of hydrogen production unit?

whats the service temperature?  

RE: piping of hydrogen production unit?

(OP)
( My English language is bad and  I am sorry for that)
Thank you Mr. blacksmith37

Are you sure that's only copper tube and have not any alloying element?
What is the color of the copper pipe? green? Yellow?
Did you have the properties of the tube? Full name (like ASTM A105), thickness, yield strength, ductility,  color,...

Please download the Copper tube handbook from this link:
http://www.google.com/url?q=http://www.copper.org/publications/pub_list/pdf/copper_tube_handbook.pdf&sa=U&ei=Hw9HTdiBDcma8QOWtrWmCQ&ved=0CBMQFjAA&usg=AFQjCNFXSEjDNH4oUWhb6Igd9ibWM1K89Q

In this book you can see the color code of copper tube.

Unfortunately we don't have any of these information about coil copper tube in the plant.
 

RE: piping of hydrogen production unit?

Our company uses a large amount of copper tube for hydrogen lines and we don't have any problems with cracking. Steel is a different story because of hydrogen embrittlement, but copper is not affected by hydrogen like that.

Could the problem is fatigue related? Is there any vibration on that particular joint where it failed?

You might also consider a flexible hose at that location. If there's any problem with a very small amount of hydrogen diffusing through the hose (which occurs to various plastic and elastomer hoses), a flexible metal hose would be advisable.  

RE: piping of hydrogen production unit?

Air Liquide has a very good online encyclopedia for this kind of stuff (http://encyclopedia.airliquide.com/encyclopedia.asp)

Hydrogen can be found here:
http://encyclopedia.airliquide.com/encyclopedia.asp?LanguageID=11&CountryID=19&Formula=&GasID=36&UNNumber=&btnMolecule.x=15&btnMolecule.y=14

It says copper is a satisfactory match, as far as material is concerned, with hydrogen but doesn't give a specific composition. From reading the other posts and looking at this information it doesn't sound like you have to worry about the specific composition of the copper pipe with regard to the hydrogen itself.

RE: piping of hydrogen production unit?

(OP)
( My English language is bad and  I am sorry for that)
now we use a copper tube, having higher diameter and so rigid in contrast with the earlier one, and when filling the capsule the rigid tube expose to stress for connceting to capsule..is it possible to have a problem in the future?

thanks for your attention.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources