×
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

Vessel ASME VIII 304H material

Vessel ASME VIII 304H material

Vessel ASME VIII 304H material

(OP)
I have to design a 10” diameter ASME VIII div.1 vessel containing hydrogen, with design temp. of 500°C and design press. of 20 barg. I should use 304H stainless steel but it’s hard to find this material on the market. A supplier propose 304/304L as an alternative material. Can be this solution correct? Which material can I use for this application? Is the 321 stainless steel suitable for this application?

RE: Vessel ASME VIII 304H material

304/304L is not suitable for replacement of 304H.

One of the pressure vessel guys will be along to provide more info.

Nick
I love materials science!

RE: Vessel ASME VIII 304H material

dedosan-

You'd reach a better audience in forum794: Boiler and Pressure Vessel engineering.

At your temperatures, there is no difference in the basic allowable stress in tension for Div. 1 whether you are using SA240 304 or 304H (or SA213 304 or 304H). So unless there is a material engineering issue with hydrogen diffusion into the steel with the differrent grades, there should be no difference. Be sure you read and understand the notes in II-D for these materials and choose your allowable stress accordingly.

jt

RE: Vessel ASME VIII 304H material

dedosan71,

The 304H grade material is necesary for the 500 deg C service temperature.  The 304L low carbon material would be limited to less than 425 deg C service, due to de-rated strength.

The straight 304 grade material with a minimum 0.04% carbon would handle the 500 deg C service, as well as would the 304H grade material.  

RE: Vessel ASME VIII 304H material

Agree with jte. Please review the allowable stress values and temperature limitations in Section II, Part D of the ASME B&PV Code. If you are going to design this vessel, you need to be familiar with Section II, Part D (but you already new this, right?)

RE: Vessel ASME VIII 304H material

One added note, austenitic stainless steel is considered impervious to hydrogen in comparison to steel or low alloy steel.

RE: Vessel ASME VIII 304H material

What is the specific components you are having trouble finding, plate, pipe, fittings, etc?

RE: Vessel ASME VIII 304H material

ApC2kp is right

luis

RE: Vessel ASME VIII 304H material

(OP)
i've troble finding fitting and pipe.
i understand that i've to ask to my suppliers 304 with minimum of 0.04% of carbon. someone told me that now fitting are supplied with a 304/304L certificate.
thank you very much!

RE: Vessel ASME VIII 304H material

deosan71,

There is increasing proportion of dual certified 304/304L material supplied on the markets.  Strength of the dual certified material is increased by additions of nitrogen and other elements to meet the ambient temperature strength test requirements for straight 304 SS.    

The 500 deg C application requires the strength imparted to the material by the minimum 0.04% carbon content, unlees there is evidence that the particular dual certified 304/304L material would have adequate strength at 500 deg C.

Better to find another supplier for SS fittings.  Your application is not the common food service or pharma grade piping design.  What fittings do you need with the 10 inch vessel?

RE: Vessel ASME VIII 304H material

ApC2Kp-

Though it may be good practice to require 0.04% C at 500°C (932°F), this is not a Code requirement until the temperature reaches 1000°F per note G12 in II-D. No changes here for the 2007 Edition.

jt

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