METHOD OF POINT WELDING Russian patent published in 2019 - IPC B23K11/10 B23K11/34 

FIELD: technological processes.

SUBSTANCE: invention can be used in point welding of metal-coated steel sheets. Test point welding is carried out to detect cracking of welded part. Metal coating is removed on surfaces of steel sheets, where occurrence of cracking is confirmed. When external cracking is detected, the edge of the coating removal area corresponds to the outer periphery of the heat-affected zone (HAZ) of the weld, but does not exceed 1.5 diameters of the equivalent circle of the place of formation of the external edge of the HAZ. In the case of internal cracking, the outer edge corresponds to the periphery of the widest HAZ weld and does not exceed 5 diameters of the equivalent circle of the place of formation of the outer edge of the HAZ. In addition, the inner edge of the circular annular area is restricted, the center of which coincides with the center of the welded point core and has diameter of 0.8 of the diameter of the weld point or less.

EFFECT: method prevents formation of cracks due to liquid metal brittleness when point welding.

8 cl, 12 dwg, 4 tbl