Distinguishing between elliptical & torrispherical domes

[guideonl]

Hi everyone,
How to determine if a pressure vessel dome is eliptical or torrispherical (from external view on a complete pressure vessel, visually/basic measuring).
Thank you.

 

[Baluncore]

A torrispherical dome will have a tighter radius of curvature around the shoulder.
The elliptical dome will have a more gentle change as the side is tangent with the ellipse.
Make yourself a curvature gauge by placing three screws in a straight line. Adjust the screws so all three contact the surface of the dome. The upper part of a torrispherical dome is spherical, so will have a constant curvature. An elliptical dome will have a varying curvature.

 

[Lnewqban]

Please, see:
https://en.m.wikipedia.org/wiki/Head_(vessel)

https://www.pveng.com/home/asme-code-design/comparison-between-head-types-hemi-se-fd-and-flat/

 

[berkeman]

Very interesting thread, thanks guys. I've learned something new!

 

[Dr.D]

Make yourself a curvature gauge by placing three screws in a straight line. Adjust the screws so all three contact the surface of the dome. The upper part of a torrispherical dome is spherical, so will have a constant curvature. An elliptical dome will have a varying curvature.

What Baluncore says is certainly true, but it must be done with care. The constant curvature is only on the spherical portion. If the gauge is too large, it may not be possible to avoid getting onto the elliptical skirt.

 

[Baluncore]

If the gauge is too large, it may not be possible to avoid getting onto the elliptical skirt.

What elliptical skirt, on which head profile ?

 

[Dr.D]

My bad, I was thinking of another configuration.

 

[guideonl]

Thank you Baluncore & Lnewqban for the information and ideas.