B16.34 2009 CF3 and CF3M update 4

[reverman]

about a year ago I had a thread asking about why the ASME committee in the 2009 B16.34 revision moved A351 CF3 and A351 CF3M to a different table that had much lower ratings than A351 CF8 and CF8M when aside from the carbon content the materials were identical.

Well today a got an supplement from the committee and the have moved CF3 back to Table 2.1 and CF3M to table 2.2 so now CF8 and CF3 have the same pressure temperature ratings and CF8M and CF3M also have the same ratings.

Which is great news. However in order to still create some confusion the committee in the same supplement completely deleted material A351 CF8C (cast grade of 347 stainless) from B16.34 . There is no explanation on why this material was removed it's been in the standard for years ( I have revisions back to at least 1988 and it was in every revision). I wrote back and hopefully I get a reason for that.

 

[hsbcn]

hi reverman, let's just hope that the deletion of CF8C is an error. can't live without that material! thanks for the update!

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[reverman]

IT was my error. They actually had CF8C on two different tables. they just deleted it off one of the tables.

 

[Flo65]

Hi,

as i have only the edition ASME B16.34-2004 could you please tell me on which group is now the CF8C and the A182 F347 and F347H.

Thank you in advance.

 

[reverman]

A351 CF8C is now group 2.11.

A182 F347 and F347H are group 2.5

If you looking at the 2004 revision you won't find Group 2.11 because it's new and the only material in it is A351 CF8C.

I would recommend getting the new revision they made several changes to many of the PT tables

 

[atif1983]

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