METHOD OF JOINING COATED PARTS Russian patent published in 2016 - IPC B23K31/02 B23K101/34 F16L13/02 

FIELD: machine building.

SUBSTANCE: invention relates to method of connection of parts with internal coating and can be used in machine building, metallurgy, equipment for nuclear power stations and space engineering. On surface of sleeve 3 and on inner surface of butt connected pipes 1 and 2 is applied by plasma-arc method coating of refractory metal and layer of zirconium dioxide. Impregnated with plasma-arc coating with mixture of oxides of Al₂O₃, P₂O₅, Cr₂O₃. Inner protective layer 4 is formed. On layer 4 fusible 5 thermoplastic layer is applied on basis of tungsten glass. Part of pipe inner surface 1 and 2 near ends is left open. Put on sleeve 3 pipe 1 against stop sleeve end 3 in layer 5 pipe 1. Put on sleeve 3 tube 2 with similar prepared end face. Pipes 1 and 2 are welded.

EFFECT: as a result no ingress of elements of coating in root weld and penetration of high-temperature aggressive medium to welded seam and surface of parts produced coating protects parts from high-temperature corrosion aggressive medium.

1 cl, 1 dwg, 2 tbl