Can API 6A flanges be used on a pressure vessel designed according ASME VIII div.1 3

[VesselFred]

Dear All,

I want to design a pressure vessel according to ASME VIII div.1 suitable for Pdesign=690 barg and Tdesign= 38oC, choice of pressure vessel material can be any material as long as the design conditions are met.

However there are no ASME flanges for these design conditions but I can use API-6A flanges.

Does this mean that I can not design the pressure vessel according ASME VIII div.1 as API flanges can not be used on a pressure vessel designed according to ASME VIII div.1.

Is my reasoning correct ? and what presure vessel design code can I use to design a pressure vessel with flanges that meet the Pdesign=690 barg and Tdesign= 38oC ?

Does anyone know ?

Best regards
VesselFred

 

[marty007]

There is nothing that says you can't use API-6A flanges.

The only complication is that the flange temperature/pressure rating is not recognized by ASME VIII-1. So, you would have to perform an Appendix 2 calculation to justify the use of these flanges. The calculation would be performed with all of the geometry from API-6A.

There is no guarantee however that it would pass the calculation. I'm not familiar with API-6A flanges, but I know for example that many ASME B16.5 flanges fail the Appendix 2 calculations at the upper ends of their pressure/temperature ratings. If you're not pushing these flanges to the upper end of their typical pressure range use, you should be okay.

 

[VesselFred]

Thanks marty007 I will give it a try and see if the flange passes the Appendix 2 calculation.

Best regards
VesselFred

 

[LittleInch]

690 barg is right on the edge of API 10000 so especially at that temperature you're probably looking at API 15,000. Big flanges.

Or did you mean 38 Deg C? eng tips doesn't do degree symbols very well....

You could also look a the compact flange range from something like Norsok / DNV. similar pressure ratings but a lot smaller.

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

 

[SnTMan]

Ten Thousand PSI. Sounds more like a Div 3 design to me.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[rtmorgan]

If allowed by your client, take a look at hub/clamp connectors and/or compact flange designs using the same style of metal-to-metal seals. Both have been used successfully in Div. 2 vessels for years.

I work for one of the manufacturers, so I am not supposed to solicit but you may want to visit the following company on the web:
Grayloc
Galperti
LTS Energy

 

[VesselFred]

Little Inch:
Indeed the temperature is 38 Deg C so API 10000 will do.

Rtmorgan:
First I want to see if the API flange will pass the appendix 2 calculation in ASME VIII-div.1

Thanks all for your response, appreciate it !!

 

[saplanti]

Please be aware that the connected (perhaps piping) flanges shall be at the same dimensions, material and the rate. You need to consider the adequate gasket as well.