×
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

Pressure limitations for ASME B31.3 and B31.11 codes ?

Pressure limitations for ASME B31.3 and B31.11 codes ?

Pressure limitations for ASME B31.3 and B31.11 codes ?

(OP)
Hi.

I was looking for the pressure limitations of those codes and I couldn't know a couple of things:

1.    I found that B31.3 code has 15[psi] as a minimium pressure and the max pressure is calcuated based on the B16.5 PN 420 (Class 2500) max pressure, that consider the material and temperature to define the max pressure, but...   the material that I'm using is API 5L x70 wich is not specified in the tables, the tables just consider the ASTM materials nomencalture (B16.5 Table 1A)...  I asumed to consider 1.1 Material Group (which gives me 6170 psig as the max pressure) but I'm not sure whether that's correct when i want to work with API 5L x70. Am I alright?

2.    For B31.11 code I found 15[psi] as a minimium pressure but I couldn't find any place where the max pressure is mentioned.
Do you guys know how I can get this max pressure?
Is the same that in the B32.3 case?

Thanks a lot for answering me.
 

RE: Pressure limitations for ASME B31.3 and B31.11 codes ?

Quote:

1.    I found that B31.3 code has 15[psi] as a minimium pressure and the max pressure is calcuated based on the B16.5 PN 420 (Class 2500) max pressure, that consider the material and temperature to define the max pressure, but...   the material that I'm using is API 5L x70 wich is not specified in the tables, the tables just consider the ASTM materials nomencalture (B16.5 Table 1A)...  I asumed to consider 1.1 Material Group (which gives me 6170 psig as the max pressure) but I'm not sure whether that's correct when i want to work with API 5L x70. Am I alright?
The maximum working pressure of your API 5L Grade X70 pipe will depend on the design temperature, pipe diameter, pipe thickness, & allowances. Note that API 5L Grade X70 is not intended for high temperature service. For high pressure piping, refer to Chapter IX of ASME B31.3

RE: Pressure limitations for ASME B31.3 and B31.11 codes ?

(OP)
I got your point but I don't mean that, I mean that I want to know what is the max pressure which B31.3 code is aplied (with its formulas to calculate thickness, reinforcements, etc), considering the material and the temperature.

For example, with an ASTM A515 gr.70 the code works up to 6170 psig (more than that pressure it's a high pressure piping), for higher presures you have to apply special rules(chapter IX).

In other words I want to know what is considered as a Pressure Piping, (from X?[psi] pressure and below Y?[psi] pressure it can be called "pressure piping"). For B31.3 and B31.11 codes.

RE: Pressure limitations for ASME B31.3 and B31.11 codes ?

B31.3 any pressure above 15 psig is pressure piping.

Maximum pressure is whatever you can calculate for your material with its specific allowable stress, the wall thickness you're using and the temperature to which it will be exposed.

For your unlisted materials it is calculated per
323.1.2 Unlisted Materials.
.....

Quote:


323.1.2 Unlisted Materials.
Allowable stresses shall be
determined in accordance with the applicable allowable
stress basis of this Code or a more conservative basis.

302.3 Allowable Stresses and Other Stress Limits
.......
(f) Unlisted Materials. For a material which conforms
to para. 323.1.2, the tensile (yield) strength at
temperature shall be derived by multiplying the average
expected tensile (yield) strength at temperature by the
ratio of ST (SY) divided by the average expected tensile
(yield) strength at room temperature.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

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