flange¦s grade

[Grammatico]

Hi, I am doing a Rerating of a pressure vessel; my problem is that I don’t know the grade of a flange (Class 600).
Does anyone know how can I do to obtain this information (consider that I haven’t got documentation of this flange), perhaps some geometric characteristic of the flange?

Thank you and sorry about my English.

 

[dcasto]

Grade of material? or are yo looking to see if you could measure the bolt hole diameter and flange thickness and look on the chart to see if it a ANSI B16.5 Class 300 versus class 300?

Go to this site if its the latter.

http://www.texasflange.com/Dimensioncutsheet.htm

 

[arto]

try these guys' catalogs:

http://www.pacificflange.com/catalog.html

http://www.weldbend.com/tableofcontents.htm

 

[SnTMan]

I believe the flange should be marked with material, spec and class information.

Regards,

Mike

 

[Grammatico]

I was looking for some information in ASME B16.5 and I found a reference of a “Pressure-Temperature Rating Table” (in table 1A). The material of my flange is an A105, so, when I go to the reference table (2-1.1) I obtain the working pressure at the working temperature. I was wrong when I said “grade of flange”, it is the “group of flange”. Now my problem is that if I change the group of flange, the area required and available of the nozzle change too. I wasn’t know that the type of flange modify the nozzles requires, does anyone know in what way the type of flange affect the nozzles requires?

thank you

 

[unclesyd]

Your flange maybe a calculated flange according to ASME VIII and not conforming to 16.5. This could be a calculated flange but driller to a 16.5 bolt pattern.

As stated above a 16.5 flange should have the Class, material, heat # , and manufacturer stamped of the periphery.

 

[SnTMan]

Grammatico, if you could explain more clearly what you are trying to do, we could help ou better.

Are you uprating the vessel? Will changing flange materials get you there? You may not necessarily need to match flange and nozzle materials.

If you do have a B16.5 flange, this should be marked on it as well.

If you are uprating, you will need to confirm the entire design, not just the flanges.

Regards,

Mike

 

[Grammatico]

Hi, I have one more question, does anyone know if ASME VIII has some recommended practice which says that the required area of the nozzle would be obtained using the MAWP of the selected flange instead of the design pressure?

Thank you.

 

[SnTMan]

Grammatico, I don't know of any such recommended practice. In some cases, this could result in running the reinforcement calculations at pressures far above the design pressure. I am assuming the temperature would be held to the design temp.

You might find anything in a customer spec however.

Regards,

Mike

 

[decode]

GRAMMA, FIRST OF ALL CHECK THE NAMEPLATE OF THE VESSEL, IF YOU FIND A NATIONAL BOARD NUMBER IN THE NAMEPLATE IT MEANS THAT THE VESSEL WAS REGISTERED WITH THE NATIONAL BOARD OF BOILER AND PRESSURE VESSEL INSPECTORS. IF SO, USING THE MANUFACTURE'S NAME AND THE NB NUMBER YOU CAN OBTAIN, PAYING A LITTLE, A COPY OF THE MANUFACTURER'S DATA REPORT, IN THIS DOCUMENT U WILL FIND ALL THE INFO YOU NEED. IF NOT LOOK FOR MARKING IN CASE OF B16.5 OR B16.42 FLANGES.

GOOD LOOK