Surface condition for flanges

[90harley]

I need to resurface the face of a custom made 14” 1500lb. flange. The flange is flat face; with additional thickness add to account for warping after welding. The flange face surface was not welded only the external and internal fillet weld to the pipe “ Slip-on” The customer is un sure of a stander surface condition after machining and has recommended use an ASME code for a guideline. I have reviewed B16.5 but I don’t see anything for Ra. Would this be under B46.1? If so dose anyone know the stander finish of a flat face 14” 1500lb. flange. B46.1 is one code I don’t have. Or, maybe I missed it in B16.5???

 

[vesselfab]

Would depend on the type of joint and gasket used.

normally it is 125-250 but could be as low as 63 or high as 500.

original drawings would tell you the machining details

 

[gr2vessels]

Ring/contact the gasket supplier and he should tell you the recommended finish for the mentioned gasket. By the way, the gasket seating coefficients are dependant on the flange face finish, hence another reason to contact the gasket manufacturer.
Cheers,
gr2vessels

 

[roca]

Is that a 1500lb or a 150lb flange?
If it is 1500lb then I am surprised that it is a Slip On flange and not weld neck for such a high pressure rating.
Also a flat face gasket does not sound right.
I would expect a RF or a RTJ

 

[90harley]

It is a 1500lb flange however it was custom made. It is set-up on an off center offset for a space restricted application. A weld neck flange was not acceptable for this application. The gasket is flat face with an engineered locking ring on the inter portion. Again customer spec.