ANSI to DIN Flange

[takiyasamsama]

Hi,

Can we simply change the the Flange type from ANSI to DIN? For example, can we simply convert ANSI #150 flange to DIN PN20? Is there any mathod do convert from ANSI to DIN?

Thanks

 

[XL83NL]

DIN flanges have been replaced by EN 1092 flanges. EN and ASME flanges dont mate. If you need a transition piece, weld a spool piece with an ASME flange on end and an EN flange on the other end.
Make sure to check the rating of both flanges.

PN ratings of EN flanges generaly dont mate with ASME flanges.

 

[gasketguru]

PN20 is not an original DIN flange - they go PN 2.5, 6, 10, 16, 25, 40, 63 bar rating etc., whereas PN20 is a metricated ASME 150 from the ISO 7005 standard, which was never a good idea in my view. The ASME flanges are converted to PN numbers e.g 20 for 150, 50 for 300 and 110 for 600 to avoid confusion with PN100. Basically these are essentially ASME flanges with metric bolting and PCD rounded off to nearest mm for instance - the problem is that in some cases things like a hard gasket (spiral wound guide ring) needs a slightly different O/D sometimes, otherwise the bolts get pushed out towards the edge of the holes. Most times this is all within tolerances and only a mm here or there, but on a few sizes and classes it can cause problems. Obviously the other original DIN flanges (10,16, 25 etc.) are different to ASME and bolting is totally different.

 

[takiyasamsama]

Thanks for your answers guys. I did my study on this topic and just now I came to know that what I was looking for was that I cannot find the equivalent for these two different flanges. In fact there are some things to consider such as the pressure-temperature rating which was like in ASME B16.5.

Please correct me if I'm wrong; PN is actually the pressure rating for the DIN / BS flanges which I can directly translated directly from ASME B16.5 table for pressure-temperature rating for example Class 150 flange's highest rating for Group 2-1.1 would be 19.6 bar therefore in DIN / BS would be similar to PN20 and for Group 2.2-1 highest pressure rating would be 15.9 bar therefore in DIN / BS would be similar to PN16. However for higher pressure rating than this would translate to PN100 and PN160 respectively.

I am not very familiar with BS and DIN standard just that recent project calls for requirement of BS and DIN standard.

 

[LittleInch]

Save yourself some serious grief and just choose one or the other, not some weird mis mash of the two.

Be aware that EN 1092 also has material grades and pressure temperature ratings associated so your example might not work.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[gasketguru]

Just to clarify, there are essentially ASME flanges and metric (DIN) flanges, where the ratings of ASME are in psi (150, 300, 600 etc.) and that rating is at elevated temperature (traditionally 300 is 300 psi at 800 or 850 deg.F depending on whether it is carbon or carbon-moly steel etc.) The DIN / metric flanges are PN numbers where the pressure is in bar at ambient temperature e.g. 10, 16, 25, 50 bar. ASME has inch bolting and DIN has metric bolts.

The PN20 you refer to is ISO 7005 where they tried to make a blend of both e.g. the series goes 10/16/20/25/40/50/63 etc. and all have metric bolts. The P-T ratings are in the standard but will be similar to the original ASME or Metric flanges from which they come. (The BS / EN standards are BS1560 and BS EN1759 for ASME flanges or BS EN 1092 for the metric flanges.) As inch bolts are still readily available I would just use ASME 150 with inch bolts rather than mess about with ISO PN20 and metric bolts which confuse the fitters on-site who take imperial spanners to what looks like an ASME flange, only to find mm bolts.