B16.5 Flange Surface Finish

[owlscreech]

I have a 1977 version of B16.5. In paragraph 6.3.4.1 it states the following about flange facing finish:

"Either a serrated-concentric or serrated-sprial finsh having from 24 to 40 grooves per inch shall be used. the cutting tool employed shall have an approximate 0.06 in. or larger radius. The resultant surface finish shall have a 500 microinch approximate roughness."

If anyone has access to the 1996 version, would you reply with what it says now.

Thanks

 

[nrp12345]

Dear owlscreech,
Cl 6.4.4.3 of ASME B16.5a-1998 reads as follows:-
"Either a serrated concentric or serrated spiral finish having a resultant surface finish from 125microin to 250microin average roughness.The no of grooves should be from 45 grooves/in to 55 grooves/in with acutting tool having a nose radius of approx 0.06in or larger."
This finish is ofcourse for RF flanges.
The surface finishes for T &G and RTJ are 125microin and 63 microin resply.

 

[owlscreech]

Thank you nrp12345.