How can i calculate the tb3 value (Min. Required thickness) for coulping 2Inch as per UG 45? 1

[Navin Kumar.A]

Dear Sir,

How can i calculate the tb3 value (Min. Required thickness) for 2 inch coupling as per UG 45?

Please suggest some answer..

With Regards,
Navin Kumar.A

 

[cbPVme]

tb3 is not calculated, it's looked up in Table UG-45.

 

[david339933]

Take Note: The General Note will be applicable in this case.

 

[Navin Kumar.A]

Dear Sir,

Thanks for your reply..
Can anyone can explain me the general notes of UG-45

ie, GENERAL NOTE: For nozzles having a specified outside diameter
not equal to the outside diameter of an equivalent standard NPS
(DN) size, the NPS (DN) size chosen from the table shall be one
having an equivalent outside diameter larger than the nozzle outside
diameter.

With Regards,
Navin Kumar.A

 

[cbPVme]

The values listed in the table are based on the outside diameter of standard pipe sizes. For example 2 NPS is 2.375" outside diameter. You have to match your nozzle outside diameter with an equivalent size pipe diameter.

Since your looking at a coupling, you might be interested in interpretation VIII-1-83-217:

Question: Are threaded couplings welded directly to a pressure vessel to be designed per ANSI B16.11 as stated in UG-11, footnote 5, Section VIII, Division 1, thus disregarding the requirements of UG-45 for nozzle neck thicknesses, since no neck exists? Reply: Yes.