PROCEDURE FOR REPAIR OF STEEL STRUCTURES BY WELDING Russian patent published in 2010 - IPC B23P6/04 B23K9/04 

FIELD: machine building.

SUBSTANCE: invention can be implemented at repair of frames of drive electric engines of locomotives operating mainly under conditions of vibration loads. The edges of the crack are grooved crack and preliminary heated to temperature 200-250°C. Low alloyed ferrite electrodes are used for production of internal layers of multi-layer welding seam. The external facing layer has thickness of h =2-3 mm; zone of thermal influence is gradually overlapped with high alloyed electrodes out of steel of austenite class of the following composition, wt %: carbon - 0.04, silicon - 0.52, manganese - 1.33, chromium - 19.5, nickel - 9.2, sulphur - 0.013, phosphorus - 0.024, iron - the rest. Also there are created compressive stresses at phase transition γ → α in a welding seam.

EFFECT: reduced level of residual stresses after welding due to artificial compressive stresses; also increased resistance to fatigue failures of steel structures operating under conditions of increased vibro-excitation.

1 dwg