Barrel housing for centrifugal fluid machines

An outer casing for a fluid-conveying unit of a centrifugal fluid machine, particularly for a multistage pumping unit of a centrifugal pump, comprising a tubular main section having a first and a second end portion;

• an annular second section at least partially installed in said main section, said second section being formed by cladding and having an end face facing one of said end portions, said end face constituting an abutment for the fluid-conveying unit of the centrifugal fluid machine, said main and second sections constituting two different bodies;
• and means for securing said second section to said main section, said securing means providing a permanent bond between said sections.

A method of making an outer casing for a fluid-conveying unit of a centrifugal fluid machine, particularly for a multistage pumping unit of a centrifugal pump, comprising the steps of providing a tubular main body capable of receiving the fluid-conveying unit of the centrifugal fluid machine;

• and forming an abutment for the fluid-conveying unit internally of said main body by joining the latter to a different annular body at least a portion of which is located inside said main body, said forming step comprising permanently securing said annular body to said main body.

A method of making an outer casing for a fluid-conveying unit of a centrifugal fluid machine, particularly for a multistage pumping unit of a centrifugal pump, comprising the steps of providing a tubular main body capable of receiving the fluid-conveying unit of the centrifugal fluid machine;

• and forming an abutment for the fluid-conveying unit internally of said main body by joining the latter to a different annular body at least a portion of which is located inside said main body, said forming step comprising depositing an annulus of molten material on the internal surface of said main body.