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ASME VIII-1 welding for internal projection nozzle on standard blind flange 3

FPPE

FPPE

Mechanical
Mar 4, 2022
194
Hi,

I have a question about the calculation in accordance with ASME VIII-1 for the configuration shown below:

Immagine 2025-01-18 122643.jpg

what are the reference paragraphs for the calculation of the standard blind flange with a 4" nozzle inserted as shown in the detail? Being a standard component but modified due to the presence of a hole, it needs to be verified in accordance with the code. Could it be calculated as a slip-on, considering the 4" pipe as if it were the shell of the flange?

Thanks in advance
 
Solution
IdanPV
FPPE said:
"Question 3: An ASME B16.5 reducing flange requiring a hub has an axial hole in the center that exceeds the size limits in UG-36(c)(3). Is it acceptable for Section VIII, Division 1 construction to use the ASME B16.5 pressure-temperature ratings for this flange without performing the reinforcement calculation per UG-39?

Reply 3: Yes"

I understand that in my case (12" blind with a 4" nozzle), I could use (referring to Table 6 of ASME B16.5) a reducing flange with the dimensions of a 12" blind, plus the hub of a 4" WN welded to above pipe. Considering that the 4" pipe has a thickness of 13.49 mm, the internal diameter of the blind would be (114.3 - 2*13.49) 87.32 mm.

In this case, no calculation would be required according to...
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Not a good design.
1) Do not use ring joint with external loads.
2) The welds on the blind flange are insufficient. Read ASME VIII Div 1,
Try another design.

Regards
 
Upvote -1 Downvote
r6155,
  • Ring joints are extensively used in high-pressure heat exchanger nozzles with applied external loads, and in our experience, no problems have ever occurred.
  • On the basis of which paragraph is the welding insufficient?
My question is quite specific,

Thanks in advance
 
Upvote 1 Downvote
Maybe try using a reducing flange 12"x4" instead of that configuration. See Table 6 of ASME B16.5.
 
Upvote 0 Downvote
My suggestions:
* Opening calculation per UG-39
* Weld sizing according to Figure UW-16.1(j) or (i)
 
Upvote 0 Downvote
@ FPPE
Why don't you read ASME VIII Div 1? The ASME CODE is clear.
How did you select the welds on the blind flanges?
Read it again and I'll tell you later.

Regards
 
Upvote -2 Downvote
"Read ASME VIII Div 1", seriously?!
Man, your suggestions are useless.
 
Upvote 2 Downvote
Trestala, IdanPV thank you very much for the suggestions.

r6155, I would like to let you know that I have read the entire Div. 1, every page, and I design things far more complex than what I asked about.
However, as you should know, unless you are a computer, it is impossible to remember everything every time (not even the ASME Authorized Inspectors I regularly work with remember everything), so I just wanted to clarify a doubt.
Thanks anyway for the suggestion; I will reread the entire Div. 1 again, and maybe I will find the answer. The ASME code is clear; it's you who are not.
 
Upvote 2 Downvote
@ FPPE
The forum is not a training course. You have too many questions on the forum. You need to learn how to use the codes.
I invest my time for free for you and others. I am not going to tell you the answer if you do not demonstrate how you designed it. If you and others do not like my method, it is your problem. There are many on this forum who are very comfortable and do not make the effort to study.
 
Upvote -1 Downvote
r6155 said:
I invest my time for free for you and others.
Click to expand...
You haven't invested anything valuable @r6155.
Your responses have only been incorrect, misleading, and irrelevant responses.
Telling others to just read the Code without pointing which part and not answering questions are not really helpful.
Maybe try not responding if you're not helping?
 
Upvote 1 Downvote
r6155, I understand your point of view, and to some extent, I agree with you.
What I disagree with is the way you interpret this perspective regardless of context.
You cannot know whether I have never opened the code and use the forum to get quick answers simply because I don’t want to reread the relevant parts of the code, or if I am a complete beginner who has never even taken a design course.
And no, I assure you that’s not the case. I’ve read a lot, studied a lot, taken courses, and (perhaps it’s my problem that I’m not good enough?) there’s always something that escapes me. I use the forum because I know there are people here with a lot of experience who can help me.
If you consider yourself one of those experienced people who can help me, great, I appreciate it.
But don’t preach to me, because I have experience too, and I don’t need another father.
 
Upvote 0 Downvote
@IdanPV
Your suggestion UG-39 and UW-16 is incomplete,
You need further studies.
 
Upvote -3 Downvote
I also tried to be polite, r6155. I didn’t mean to be aggressive, and I’m sorry you felt insulted. I was just trying to explain why I thought you were making a mistake in how you formulated your responses.
Even though you’re not my father, we can still start over and have a productive discussion on this forum.
 
Upvote 0 Downvote
@FPPE,
I've found some old threads from this forum that might help you:

Openings on Blind Flanges (Bolted Covers) - Boiler and Pressure Vessel engineering

I'm working on a vessel that will have a 6" Class 600 (1000 psi @ 400F) Blind Flange on a nozzle that requires a Centered Opening (1 1/2" NOM) and (6) 1/2" NPT Tapped Holes surrounding this center opening (Image attached). I've read ASME B16.5 Table 6 and the 1 1/2" Centered Opening complies...
www.eng-tips.com www.eng-tips.com

Openings in blind flanges - Boiler and Pressure Vessel engineering

I am required to make 4 x 1/8" NPT holes in a class 150 blind flange and would like to know if the rules of UG-36 (Openings in Pressure Vessels) apply to the design. Thank you.
www.eng-tips.com www.eng-tips.com

Opening in standard blind flanges - ASME (mechanical) Code Issues

I am designing a pressure vessel using compress software .the PV is 24" OD and has a bolted cover. we want to use standard slip on flange & blind flange but we need to make an opening in the blind and we can't do it in compress. 1) can we use a UG-34 cover with the same dimensions of standard...
www.eng-tips.com www.eng-tips.com

The last one seems to be very helpful
 
Upvote 0 Downvote
Thank you very much IdavnPV! The last one is exactly what I needed.
 
Upvote 0 Downvote
I have read everything, and from the following:


"Question 3: An ASME B16.5 reducing flange requiring a hub has an axial hole in the center that exceeds the size limits in UG-36(c)(3). Is it acceptable for Section VIII, Division 1 construction to use the ASME B16.5 pressure-temperature ratings for this flange without performing the reinforcement calculation per UG-39?

Reply 3: Yes"


I understand that in my case (12" blind with a 4" nozzle), I could use (referring to Table 6 of ASME B16.5) a reducing flange with the dimensions of a 12" blind, plus the hub of a 4" WN welded to above pipe. Considering that the 4" pipe has a thickness of 13.49 mm, the internal diameter of the blind would be (114.3 - 2*13.49) 87.32 mm.

In this case, no calculation would be required according to ASME VIII-1, and we can simply follow the pressure-temperature rating of B16.5.
Is my interpretation correct?
 
Upvote 0 Downvote
Kinda curious too on how you designed the weld. The throat thickness should be 9.45mm (0.7*pipe thickness). So how did you get 8mm?
 
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