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Pipe End Cap Design Thickness 3

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Tomy-Met

Materials
Mar 27, 2019
15
Gents!
I am looking for your expert advise, please help.
We need to isolate our distiller from boiler by cutting reheater line & installing and and end cap.
Line Material: 10CrMo910, Dia: 609mm, Thick: 22.2mm, Pressure: 41bar, Temp: 530c
I have calculated required thickness for hemispherical head (SA-387 Gr-22) as : 12.09mm (Calculation attached)
Please advise are there any other factors which i should consider or simply i should order head of this thickness?
 
 https://files.engineering.com/getfile.aspx?folder=b4aeb275-b75f-4960-9fdc-3c09ee981ddc&file=Calculation_for_Head_Thickness.pdf
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There may be (a lot of) other factors, but we dont know, as too many details have not been provided, to provide some good pointers.
Whats the design code? Is this a modification, or adjustment of something that only in construction? Do you have things like nozzle loads? Are there any other loads working on this head?

A simple calculation like the one you posted is a good start, but a caluclation should be done with the overall picture in mind. For example, we know nothing about the layout of the vessel, and how that may affect your JE (Joint Efficiency). Try to provide more details, and well see what we can do - but with the current set of data, thats almost impossible.
 
This sounds like a pipe no?

Why are you trying to design a pressure vessel end cap when you can just buy one to ASME B 16.9?

Design code applicable here is?




Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
@LittleInch Thanks for the reply.

Actually we want to isolate many piplines of various sizes ranging from NB 80 to NB 1400,these lines are between boilers and distillers, distillers were decommissioned so isolation was required on boilers side live lines.
I think ASME B16.9 shall not cover large sizes like NB 600, NB 1400, that's why i am considering vessel head for larger pipes.

I have another concern too, material for piping is as per DIN standard e.g 10CrMo9-10, 15Mo3, St37-2 etc can i use some equivalent ASTM material by comparing chemical composition and Tensile strengths.

Is there any relation between vessel head type (hemispherical, ellipsoidal) and design pressures? My question are any pressure limits for a specific head type?


 
@XL83NL Thanks for highlighting other fronts to consider.

These boiler re-heater and superheater lines going to desalination plant which were decommissioned. Now we need isolation at boiler side by cutting and installing end caps at various locations. Most of the locations are branch type.

Line sketch is drawing is attached for your expert review.
 
 https://files.engineering.com/getfile.aspx?folder=24434600-e2ef-4cb3-9359-abb178ffc734&file=Sketch.pdf
Weld neck flange and blind flange instead?

What is the piping code? What fitting standard does it reference?

I don't recognise that material but it looks fairly exotic.

NB 1400 for a pressure pipe is pretty big, but end caps will exist in this size.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
These modifications are to piping, so start with the piping code. This might lead you to B16.8 then on to ASME BVC for the design of a cap.

But also you are making modifications to the piping. This will changed the stresses with the piping and the needs to be reanalysed.
 
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