METHOD OF ARC-WELDING IN WIDE-LAYER SURFACING UNDER WEAR-RESISTANT COATING FLUX ONTO CYLINDRICAL PIPE Russian patent published in 2020 - IPC B23K9/04 B23K9/18 

FIELD: methods and devices for metal processing.

SUBSTANCE: invention relates to electric arc surfacing and can be used in reconditioning of worn-out parts of steel pipes, in particular, drill pipes, as well as for production of wear-resistant built-up layer on cylindrical pipes. In the method of arc-surfaced wide-layer surfacing of a wear-resistant coating on a cylindrical pipe, surfacing is carried out in two layers by annular rollers. They are formed by a split arc by two electrodes installed along the generatrix of the pipe. First electrode forms annular contacting rollers of the bottom surfacing layer, and the second electrode forms annular rollers of the overlaying layer of surfacing. Also simultaneously forming two annular rollers: annular roller of coating layer on surfaced annular roller of lower layer and surfacing of next annular bead of lower layer in contact with said formed circular roller of lower layer.

EFFECT: providing high quality of the coating by eliminating pores and reducing the probability of formation of microcracks in the deposited layer while providing higher weld deposition efficiency.

4 cl, 1 ex, 1 dwg