2:1 ellipsoidal head is designed in a 2:1 ratio, this means that in this type, the diameter to the depth ratio is 2:1. The shape of this ellipsoidal head is more economical, because the height of the head is just a fraction of the diameter. As The Meridian curvature change of ellipsoidal part of the tank head is smooth and continuous, the stress distribute uniformly. The elliptical tank head is the economical solution for medium pressure tanks due to the reduced metal thickness requirement.