To be precise, we cannot really equate the two different standards, even above 150# of ANSI. The best reliable action will be to look into EN 1092 part 1 to 4 , and look at the pressure / temp limitation table. Take note of the name diff. Working pressure vs. Allowable pressure. And the special note on agreement between manuf. and purchaser.
The above is due to the reason that to my awareness, I have not found any official standard stating the equivalent of each other. All equivalent tables are provided by only manufacturers who may or may not guarantee what they write in thier catalog explicitly. Just to have a general idea such tables can help but not for practical technical solutions.
It would be interesting to just have a look at the dimension variation of a choosen flange between EN and BS and ASME.
I like to make a reference here of a case I came across. A butterfly valve manufacturer who supplied sizes of 36", 48", 56", 64" ANSI double flanged ends. I found the flanged end OD and thickness was reduced by 40mm on an average, just around 6 to 7 mm near the bolt hole....! When asked he says the flange will not fail even at full rating condition. By which he simply violates the ANSI and says still he can satisfy the PT limits of ANSI and it is his standard practise to follow the reduced dimension. The valves are ready for dispatch and now considering the big cost involved in cancelling the order and time delay, it had to be approved with the gaurantee letter. In practice it does not have any problems because the operating conditions are below the rating limits, but not a safe design. Moreover it is a big cost saving for the manufacturers considering such big material, weight, machining cost reduction. The vendor is Tyco.
So take caution while considering such equivalent ones and even the ones where even the ANSI is violated as we tend to overlook the standard dimensions on the drawings.
Regards,
Kannan
Germany.
| "Agrawal Sunil \(Mumbai -Stequ\)" <s.agrawal@ticb.com> Sent by: piping_valves@yahoogroups.com 15/10/2008 06:33
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Can any one guide me what is the ANSI equivalent rating for PN below 20 (PN 2.5, PN 6, PN 10, PN 16)?
Thank you…
Best regards,
Sunil S. Agrawal
Static Equipment Dept. (STEQU)
Engineering & Design Tecnimont ICB
101/102, Interface-11, Link Road, Malad (w), Mumbai - 400 064 ( +91.22.6777.7237 * s.agrawal@ticb.com
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Agrawal Sunil (Mumbai -Stequ)
Sent: Thursday, July 17, 2008 11:33 AM
To: materials-welding@googlegroups.com
Subject: [MW:934] RE: 932] ANSI v/s PN Rating flange - Comparision table
Please find below the comparision:
PN ANSI rating
20 150 #
50 300 #
68 400 #
100 600 #
150 900 #
250 1500 #
420 2500 #
Source: Handbook of TC
I am not sure about reliability of above data and hence I request other member to contribute.
Best regards,
Sunil S. Agrawal
Static Equipment Dept. (STEQU)
Engineering & Design Tecnimont ICB
101/102, Interface-11, Link Road, Malad (w), Mumbai - 400 064 ( +91.22.6777.7237 * s.agrawal@ticb.com
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Darji Nilesh (Mumbai - Machinery)
Sent: Thursday, July 17, 2008 10:19 AM
To: materials-welding@googlegroups.com
Subject: [MW:932] ANSI v/s PN Rating flange - Comparision table
Can any one provide me a subject table.
Nilesh.
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