ASME Standard for 56" and 72" Flange and Bolt sizes

[albertaengineer]

I am looking for the dimensions for bolt and nuts for 56" and 72" 150# Wn Flanges.

I am to torque these nuts, and do not know the dimensions

I am unsure of which ASME standards to look at.

Thanks.

 

[SnTMan]

albertaengineer, if possible you should first probably identify what you have. For example ASME B16.47 covers flanges 26" thru 60" NPS. Your 72" flange is not likely to be one of these. There are (or WERE) "industry standard" flanges listed in 125# up to 96" and 175# up to 72" in my old Taylor Forge book. There are also AWWA flanges in these size ranges although I don't know how they are rated or whether they are "weldnecks".

You could also just determine your bolt sizes and shoot for a stress of about 50,000 psi. You should probably assure yourself that the bolted joint will take it without crushing the gasket or deforming the flanges.

There is much fuller discussion of this issue in other threads on this site. Have you tries searching this and some of the other forums (fora??)?

Regards,

Mike

 

[JStephen]

The AWWA flanges are normally hub-type or plate flanges, not weld-necks. They're also normally flat-faced.

 

[JohnBreen]

Hello Albertaengineer

Following up on SnTMan's comments, ye olde Ladish catalog listed 72 inch Class 150 weld neck and slip-on flanges as having a bolt circle of 77.75 inches (64 bolts) and the bolt hole diameter is 1.25 inches. I think this implies 1 inch bolt diameter.

For the Class 150, 72 inch weld neck the outside diameter (O) is shown as 80 inches. The hub height (Y) is shown as 6.625 inches and the flange thickness (Q) as 3.625 inches. The raised face is shown as 0.063 inch.

The Ladish catalog also shows data for Class 300 flanges up to 48 inches.

Regards, John.