Commonly designed Pressure vessel used semi hemisperical end compared to Hemispherical end as it is easier to fabricate. Typically pressure vessel were designed according to the required codes and standards as required by the end user. Ideally , for highly pressurised vessel up to 200 barg , hemispherical end is used because it will reduced the required thickness almost half compared with semi-hemisherical end. This is due to the hoop stress (hemispherical end) almost half than the semi hemisperical end vessel.

example : will be given later....?

Briefly, several codes giving the difference explanation in thickness calculation for the thickness of the head(end) of pressure vessel.

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