Design of Obround flange mounted on glass window 3

[nashraf]

I am planning to design a 300mm long and 120 mm square (50 mm thick) chamber that will be pressurized to a pressure of 100 bars before injection of diesel fuel into the chamber. To visualize the flow of diesel jet coming out from the nozzle I am planning to put four large obround windows 90 mm X 200 mm. Bolted obround flanges with dimensions 150mm OD 70 mm ID X 280mm long will be used to put the windows in place.

Does anyone have any source for the design of an obround bolted flange according to ASME or anyother standard (AS preferred) with pressure being applied from inside from the viewing window

Thanks

 

[arto]

Look in appendix 13 ASME B&PV Code Sec. VIII Div.1
@ 100 bar [~1500psi] you may end up with a rather beastly vessel - maybe use a cylindrical chamber with round viewports? [could use filler blocks for rectangular combustion chamber]

These guys make test vessels with viewports:

http://www.pressureproducts.com/researchmain.htm

 

[nashraf]

OOps, i made a mistake. I should not use obround flange here but the best word could be a cover plate or a retainer for obround or oblong window. Arto! can i use appendix 13 ASME B&PV Code Sec. VIII Div.1 to design a cover plate or window retainer.

Thx

 

[prex]

By examining the dimensions you gave, I must assume that the four windows are placed each one on a side of the square and longitudinally at the same location.
I'm afraid that, if this picture is correct, you'll have no chance in designing the beast, as there will be no metal to resist pressure forces, unless you put studs across the windows.
To say more, this would be true even with a single window on one side of the square. To visualize this just sketch the square cross section with one side practically absent, picture the pressure load on the two adjoining sides and answer the question: how this structure, that is equivalent to a box with only three sides, will resist pressure forces?

prex

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[nashraf]

My design is similar to

http://www.pressureproducts.com/researchmain.htm

with the exception that the chamber here is a circular one whereas i am using a square chamber with round corners and i am putting one window on each side. In this case the window is reatained by 6 bolts by a window retainer (may be called as flange) whereas i am using 20 bolts to fix the window in its place by the window reatainer. My question is that can i use appendix 13 ASME B&PV Code Sec. VIII Div.1 to design the window reatainer (can be called as flange).
Thx

 

[prex]

I must insist, your design is by no means similar to that picture.
If my understanding is correct you have a window 90 mm wide on each wall of a square that is 120 mm wide (internal dimension of course). This means that you have metal only in the corners and I wonder whether this will be sufficient to resist longitudinal stresses (though 50 mm thickness is quite a lot).
Circumferential (or transverse) stresses must be resisted by the full metal available upstream and downstream of the windows, but also there you have only 50 mm left on each side of the windows.
As you can see the proportions of the pictured vessel are quite different.
Concerning your question, the retainer is a flange, so you would design it per App.2, not App.13. Of course I suppose you don't want to use the retainer as a wall reinforcement: this is not impossible if suitable design choices are adopted, but is not allowed under ASME VIII.

prex

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