| 摘要 |
welding, namely electric arc welding of products of cast iron with spherical graphite, possibly in gas-oil industry, power generation, ship making, municipal building. SUBSTANCE: method comprises steps of preparing edges of product for welding; preliminarily heating them up to temperature (200-600) C at rate (3- 7) C/min; performing electric arc gas-shield welding of root seam and other seams at electric current density (25-35)A/sq. mm at rate (6- 10)m/h; realizing heat treatment of welded seam by heating it up to temperature (800-850)C with rate no more than 10C/s at isothermic curing for (3-5) min and at air cooling until environmental temperature. EFFECT: maximally lowered residual stresses, cementite decomposition, elimination of brittlement of grain boundaries of welded joint structure. |
