Apparatus for manufacturing spherical metallic vessels or hemispherical vessel heads

Abstract

Abstract A spherical container or a hemispherical head for a pressure vessel, is formed integrally of deposited weld metal. A first turntable is rotatable about a substantially horizontal axis which constitutes one diameter of the sphere, and a second turntable is rotatable about a substantially vertical axis which constitutes another diameter of the sphere perpendicular to the first diameter. A small spherical metallic segment constitutes a starting piece, and has a wall thickness equal to that of the vessel to be formed, the segment forming the base of a solid central angle of the sphere. The segment has a tapered step extending completely around its peripheral edge and having a maximum height equal to the thickness of a layer of weld metal to be deposited and a minimum height equal to zero, thus forming an abrupt step. The segment is mounted on the first turntable for symmetrical rotation about the first diameter of the sphere. The second turntable supports an electro-slag welding apparatus for revolution about the mentioned vertical axis, and a channel-shape copper block is also mounted for revolution about the vertical axis and is arranged to embrace the periphery of the segment, this block forming a backing bar for the deposited weld metal and flux. The weld metal is progressively deposited along the peripheral edge of the segment in the form of a continuous strip comprised of superposed convolutions whose width is substantially equal to the wall thickness of the vessel to be formed and whose thickness is substantially equal to that of the step. The rate of rotation of the segment is coordinated with the rate of deposition of weld metal, and the rate of revolution of the welding apparatus and of the backing bar is coordinated with the progressive change in diameter of the vessel being formed by the deposited weld metal.

Inventors

• 👤 A Ujiie

Bibliographic Details