Ellipsoidal V.S Torispherical
Ellipsoidal V.S Torispherical
(OP)
Dear All,
I have a vessel with ID=3500mm,DP=55barg, DT=300c,my recommendation for head is 2:1 ellipsoidal but our fabricator considered an approximation based on UG32(d)with knuckle radius0.17D and a spherical radius 0.9D.Thats acceptable but for thickness calculation he has applied 0.9D instead of D at ellips. formula.whats your idea?is it correct?and why?
Thank you very much
I have a vessel with ID=3500mm,DP=55barg, DT=300c,my recommendation for head is 2:1 ellipsoidal but our fabricator considered an approximation based on UG32(d)with knuckle radius0.17D and a spherical radius 0.9D.Thats acceptable but for thickness calculation he has applied 0.9D instead of D at ellips. formula.whats your idea?is it correct?and why?
Thank you very much





RE: Ellipsoidal V.S Torispherical
D is, as defined in UG-32(c), the inside diameter of the head skirt, and stays as such. The approximation permitted in UG-32(d) is only a matter of how to fabricate the head and of checking its shape, the calculation stays exactly as if it was an ellipsoidal.
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RE: Ellipsoidal V.S Torispherical
I asked him about this matter and the fabricator clarified that he applied K=0.9 in the ellips. cal. formula with the specified h.is this a correct answer?
Thanks
RE: Ellipsoidal V.S Torispherical
By the way there is no h (height?) in the formula, so can't understand what they are doing.
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http://www.xcalcs.com : Online tools for structural design
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RE: Ellipsoidal V.S Torispherical
depth of head (h) is 958mm.
Thanks
RE: Ellipsoidal V.S Torispherical
Can't comment anymore without some clear and complete data.
prex
http://www.xcalcs.com : Online tools for structural design
http://www.megamag.it : Magnetic brakes for fun rides
http://www.levitans.com : Air bearing pads
RE: Ellipsoidal V.S Torispherical
As this head is deeper than a 2:1 ellipsoid, it may be true that its thickness is lower, but to prove this according to the code the correct procedure is in 1-4.
prex
http://www.xcalcs.com : Online tools for structural design
http://www.megamag.it : Magnetic brakes for fun rides
http://www.levitans.com : Air bearing pads