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Participant

Join Date: Feb 2010
Posts: 3

# Converting PN Values to ANSI Flange Ratings

02/24/2010 10:31 PM

I have some question about how to convert to PN value to ANSI flange rating or class as below.

1. Is it different when the material different? For example bronze, cast iron, ss or pp?

2. PN value seems to mean the flange rating, but in case the end type is screwed, then what's the meaning of PN value such as PN 16/PN25?

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Anonymous Poster
#1

### Re: How to convert PN value to ANSI flange rating/class?

02/25/2010 3:06 AM

1. PN values are for the flange. The ANSI B16 Series covers the cast iron, Steel(s), Bronze and copper : 16.1,16.4 (Cast iron), 16.3 (malleable iron) etc.

2. The PN is applicable for threaded flanges too.

3. For Conversion PN to Class refer here

Participant

Join Date: Feb 2010
Posts: 3
#2

### Re: How to convert PN value to ANSI flange rating/class?

02/25/2010 3:59 AM

Thanks a lot. How about the other PN value convert to class? Such as PN 6/10/16/25/32. I can not find the value from the table.

Besides, I knew we can calculate the class rating for example PN 16 = 16 bar = about 232psi, so we can choose class 300 as the class rating. But such calculation can not fit the table as per you issued. Which one is correct? And how to identify?

Anonymous Poster
#3

### Re: How to convert PN value to ANSI flange rating/class?

02/25/2010 5:43 AM

All are not exactly equivalent, based on service condition you have to select the flange.

Also it may be noted that they are not interchangeable (ANSI flange won't match the nearest DIN flange)

Thirdly the ASME may not permit the DIN flanges. The EPV however will accept the ANSI. (Bias )

Just for a few links on DIN- this has a few and this has much more details (including DIN Numbers)

Maryland metrics also has lot of details on DIN flanges, go to it's home page, where the pressure and temperature ratings are also available.

Participant

Join Date: Feb 2010
Posts: 3
#4

### Re: How to convert PN value to ANSI flange rating/class?

02/26/2010 4:29 AM

Thanks very much for your furthering explaination, now I have a much clear idea about PN & ANSI flange rating.

Anonymous Poster
#5

### Re: How to convert PN value to ANSI flange rating/class?

04/16/2010 4:39 PM

You would not use a 300lb class flange. You would use a 150lb class they are rated to 285 psi.

Anonymous Poster
#6

### Re: Converting PN Values to ANSI Flange Ratings

06/06/2010 3:55 PM

PN specify the pressure ratings