METHOD OF STRAIGHTENING SHIP CRANKSHAFTS Russian patent published in 2025 - IPC C21D7/13 C21D9/30 

FIELD: ships and other floating crafts.

SUBSTANCE: invention relates to the ship repair industry, namely to methods for straightening ship crankshafts when they become bent during operation, in particular when restoring crankshafts of internal combustion engines. Ship crankshafts straightening method includes the shaft installation on the supports, determination of the shaft main journals deflection direction and value and the shaft subsequent bending in the direction opposite to the initial bending, the crankshaft fixing on the supports by the bending along the main journals axis upwards, local volumetric heating of main journal to achieve shaft material relaxation temperature of 450-650 °C with heating rate of not more than 150 °C/h, then, with the continuous thermal action, performing the mechanical action on the deformed portion of the shaft in the direction opposite to the initial bending, for an hour, then shaft is subjected to cooling in closed room at set ambient temperature from 18 to 25 °C and shaft continuous rotation with speed of 3 rpm.

EFFECT: improving accuracy of straightening of shafts and fatigue resistance of the repaired shaft.

1 cl, 1 ex