Do ASME B16.5 flange ratings include NEMA SM23 swings?
Do ASME B16.5 flange ratings include NEMA SM23 swings?
(OP)
NEMA SM23 allows variations in steam pressure and temperature to exceed maximums by 20% pressure and 50 deg F. Do the ASME B16.5 ratings include these swings or are the B16.5 values absolute maximums? For A-217 GR WC9 (material group 1.10) Class 1500# at 950 F, the allowable pressure is 1885 psig. If the piping design requires 1750 psig @ 950 F is a 1500# flange acceptable or do you have to apply the NEMA variations? Applying the +50 F temperature variation would force a the design into a class 2500# flange as a 1500# flange at 1000 F has a rating of only 1305 psig.





RE: Do ASME B16.5 flange ratings include NEMA SM23 swings?
ASME B16.5 is for pipe flanges.
As long as your design pressure @ temperature falls below the ASME B16.5 class, that is it, as I interpret it.
Perhaps my mechanical colleagues can provide more information.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Do ASME B16.5 flange ratings include NEMA SM23 swings?
NozzleTwister
Houston, Texas
RE: Do ASME B16.5 flange ratings include NEMA SM23 swings?
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
RE: Do ASME B16.5 flange ratings include NEMA SM23 swings?
Nozzle is correct.....it is the piping code of record that defines maximum pressure/tempersture transients above design
Give him a star !!
-MJC