×
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

ASTM Vs SAE Fasteners

ASTM Vs SAE Fasteners

ASTM Vs SAE Fasteners

(OP)
I've tried asking this on the ASME (mechanical) part of this site a couple of weeks ago. Nothing so far, so I'll try it here.

Is substitution allowed for B7 bolts/studs & 2H nuts with the much more readily available SAE Gr 5 and/or Gr 8 fasteners for pipe flanges under codes like the ASME B31.1 Power Piping Code?

All of the codes and reference material I can find ONLY refer to ASTM A-193 bolts/studs and ASTM A-194 nuts. I can find no "equivalents" for these, yet I continually see SAE Gr 5 & Gr 8 (usually Gr 5 because they're cheaper) used for flange bolts on piping in a lot of general industry plants (all of the steam systems I'm referring to are below 300 PSIG, most are 250# or less, and the compressed air systems are typically 125#).

I don't  think that the substitution of ASTM fasteners with SAE is proper, but I've been wrong before. And I cannot honestly say that I'm aware of any catastrophic flange failures due to SAE fasteners being used in these pressure/temperature ranges. The inspection authority is unable or unwilling to give anything like a clear answer.

Does anyone have an opinion on this? Can you point me to some specific documentation?

RE: ASTM Vs SAE Fasteners

An air system is not power piping, yes it may have a lot of potential for release of energy, but it is not covered.  I believe that small piping is exempt from the requirements of B31.1.

RE: ASTM Vs SAE Fasteners

(OP)
In Ontario, compressed air systems where the safety valves lift over 15 PSIG, fall under ASME B31.1 if they are over 3/4" (any pipe size if they are welded or brazed).

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