ASME B16.5 Flange Ratings

[roca]

Hi All
I have also posted this under the ANSI Eng Tips forum - but it is applicable to ANSI and ASME

I found this post:

https://www.eng-tips.com/viewthread.cfm?qid=181686...

in my search to a problem I am currently looking at.

My question is was there an error in the 1973 ANSI B16.5 150# flange table for A-105 materials?
If I look at the 1973 version versus the 2017 version, using imperial units we get the following:
Temp °F - 1973 Version - 2017 Version
500F 230psi 170psi
600F 210psi 140psi
650F 205psi 125psi

The differences in allowable pressure is quite large and I can';t believe that the 1973 values are correct.

I seem to remember from around that time that there was an error in the published 1973 tables - yes I am that old!!

I have looked in the history blurb of the 2017 version of ASME B16.5 and it states: "At the same time, comments from users and changes in the ASME Boiler and Pressure
Vessel Code led to significant revisions in the Class 150 rating basis and....etc"

Any clues?

 

[XL83NL]

Maybe this thread with BJI’s post can help you?

https://www.eng-tips.com/viewthread.cfm?qid=454965

 

[roca]

Thanks XL83NL
I actually found the historical details document posted by LittleInch myself via a google search.
The history doesn't actually say what was done/changed in the ANSI standard, but obviously the published ratings in the 1973 version were incorrect.
Like I said above I seem to have a niggling memory of this and there was a bulletin sent out at the company i was working for (Fluor at that time) that the 150# table was incorrect.

 

[XL83NL]

No, LI’s post is interesting, but (as I said) BJI’s post is the one to look out for.