Process Equipment and Plant Design
A stuffing box is used for

Absorbing the contraction/expansion of pipeline due to temperature changes
Prevention of fluid leakage around moving parts
Reducing the resistance of fluid flow
Facilitating smooth opening and closing of a valve

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Process Equipment and Plant Design
Generally, elliptical dished heads

All of these
Resist half the pressure rating compared to hemi spherical head provided on the cylindrical shell of the same thickness and diameter
Are manufactured on 2:1 ratio of major to minor axis and is recommended to be used for pressure vessels operating above a pressure of 1.5 MN/m²
Are approximately as strong as seamless cylindrical shell having the corresponding I.D and O.D

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