Back to basics calculation for ASME Pressure Vessel with Flat Head

[Chrissy123]

Hi all - I'm going back to basics with my pressure vessel analysis and starting with ASME to calculate the acceptable operating pressure of a pressure vessel. My model is simple - flat head cylindrical. Length of cylinder 500mm, inside radius 254mm, cylinder shell thickness 100mm, flat head thickness 10mm, material properties, E=107GPa, poissons =0.3, yield 207 MPa. From the ASME Boiler and Pressure Vessel Code, Section VIII, Div. I, UG-27, the thickness of a cylindrical shell under internal pressure must be no less than
𝑡 = 𝑃𝑅/(𝑆𝐸 − 0.6𝑃) but this is for the thickness of the shell of the cylinder. I have found this equation for the thickness of the flat head:

.

I'm making the assumption that Corrosion is zero and welding efficiency is 1 (just for this simple calcuation), C=0.33 for a weld

d = inner diameter = (2*inside radius) = 508mm, S=allowable stress which from this forum is 2/3Yield = 138MPa,

So re-arranging the equation gives a formula for Acceptable Operating P as P=(t^2*S*E)/(d^2*C) = (10^2*138*1)/(508^2*0.33) = 0.16Mpa .... is that a reasonable ball-park figure?
thanks,

 

[SnTMan]

Chrissy123, given your assumptions your arithmetic is correct.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Chrissy123]

thank You

 

[dhengr]

Chrissy123:
And, I’m sure that SnTMan would agree that, three winks, a nod of the head and a finger up the nose allows for at least two bad assumptions, and a satisfactory/perfect outcome.

 

[SnTMan]

The problem with sloppy work is that the supply FAR EXCEEDS the demand