The generatrix forming the elliptical head is smoothly connected by a 1/4 ellipse line and a short straight line parallel to the axis of rotation. Therefore, this head is composed of a half ellipsoid and a cylindrical short section of height h (called It is composed of the straight side part of the head. The ratio of the surface depth h1 of the standard elliptical head to the nominal diameter of the head is 1:4. The geometric shape of the standard elliptical head is roughly as described above, but most of it is made according to the required size of the head.