REPAIR METHOD OF A CASING OF A THERMOCOUPLE OF A GAS-TURBINE PLANT Russian patent published in 2020 - IPC B22F3/105 B22F5/00 B33Y10/00 B23P6/00 B23K26/342 B33Y80/00 

FIELD: turbines or turbomachines.

SUBSTANCE: invention relates to additive technology of recovery of parts of gas turbine plants. Method of gas turbine plant thermocouple case repair includes installation and fixation of thermocouple case to appliance in vertical position, restoration with additive material of thermocouple case by laser surfacing. Mechanical part of the thermocouple case is mechanically removed to the height of the defect; the external and internal surfaces of the wall of the thermocouple case are cleaned. Laser surfacing in protective gas medium of end surface of casing is performed by successive application of layers, each of which is obtained by application of single circular rollers with supply of filler material to weld-on zone coaxially to laser beam. Rollers are applied in series in circular rows from outer surface to inner surface in direction of symmetry axis of thermocouple case wall. Roller overlap between adjacent annular rows in direction of symmetrical axis of thermocouple case wall makes 50%. Required number of layers is applied until complete recovery of thermocouple case dimensions. Welding of outer and inner annular rolls of each layer is made at angle of 15° relative to normal parallel to axis of symmetry of wall of thermocouple case, then thermal treatment in vacuum, mechanical treatment and capillary control. As filler material there can be used metal powder of wear-resistant alloy on cobalt base.

EFFECT: higher quality of repair of thermocouple case with degree of wear of wall of thermocouple case at interface of different height and intensity of wear, up to through.

3 cl, 6 dwg