How can I use SA-181 forgings material for flanges?

[NicuG]

I can't use SA-181 forgings materials for flanges. I fix it in the ASME material tables (ex. SA-181 CL.70) and, curriously, I find it in the material list of nozzles pipe or pad, but I can't find it in the material list of ASME B16.5/16.47 Flanges.
Can any one offer a solution or an explanation?
Thanks.

 

[doct9960]

Explanation: A 181 is not in Table 1A (List of Material Specifications) of ASME B16.5 nor in Table 1 (List of Material Specifications) of ASME B16.47.

 

[vesselfab]

yes

a-181 cover "non-standard" forged components for fittings valves, etc.

standard forged parts...b16.5 b16.47 etc have been moved to a-105

this happened many years ago

are you still seeing flanges made in a-181 where you are?

 

[eliebl]

I think that the last time SA-181 was usable for flanges (B16.5) was early 80's.

Be cautious in re-rating vessels with these flanges because of the potential of different ratings depending on the class of material.

One option may be calculating an appendix 2 flange but your AI may not agree. If calculations are the route you want to take then the flange CANNOT reference B16.5.

EJL

 

[TomBarsh]

wow, you guys are FAST!

Note as well that the ASME Code specifies the particular edition of B16.5, etc, that is acceptable for any particular Edition/Addenda of the Code. See Table U-3. COMPRESS uses the versions of B16.5/B16.47 as defined in Table U-3 for the selected ASME Code Edition/Addenda.

The materials listed in these standards are known to vary over time.

Even pressure-temperature ratings may change between Editions.

In fact, last week I ran across a material that had its material group changed in the latest Edition of B16.5. I don't remember what it was but it surprised me.

Tom Barsh
Codeware Technical Support

 

[eliebl]

Try SA-350 LF3. Was Group 1.2 and is now Group 1.1. Lowered the pressure rating.

EJL

 

[TomBarsh]

A follow-up to this thread with three comments:

1- COMPRESS contains separate databases for materials listed in ASME Section II Part D and materials for ASME B16.5/B16.47 flanges.

2- Materials for ASME B16.5/B16.47 flanges are restricted to those listed in the material tables of the flange standards. The Standards contain only a small subset of the materials listed in Section II Part D. Also, note that the Editions of these standards varies with the Edition/Addenda of Section VIII Div 1 (see table U-3). COMPRESS uses the Edition of the flange standard as listed in Table U-3 for the selected Code. There will be differences in flange pressure-temperature ratings between Editions of the standards.

3- For use with re-rating of older vessels for fitness-for-service consideration COMPRESS now provides some "historical" flange materials that were in common use years ago. The COMPRESS History document (select the Help menu, View History command) describes this:

ASME B16.5\B16.47 Fitness for Service Materials
The following materials are now available for all ASME B16.5/B16.47 Editions. These materials should only be used in a Fitness for Service (FFS) evaluation of existing vessels when permissible per the governing ANSI document applicable to the initial design of the vessel.

New Flange Material Specification ASME B16.5/B16.47 Material Group Assignment
A 181-I (FFS rating only) 1.4
A 181-II (FFS rating only) 1.1
A 181-60 (FFS rating only) 1.4
A 181-70 (FFS rating only) 1.1
[6846]



Tom Barsh
Codeware Technical Support