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Power shafts for large ships

Power shafts for large ships

Product Description Power shafts for large ships are integral forged bars that connect the main engine to the propeller or electric motor. Starting from vacuum-degassed carbon or low-alloy steel (C45, 34CrNiMo6, 42CrMo4), we upset forge, roll and machine shafts 80–1 200 mm diameter, up to 24 m single-piece length and 80 t finished weight. Full CNC turning, deep-hole boring and spline milling meet IACS UR M68 and customer drawings.   Performance Quench-temper produces 450–650 MPa yield, 700–900 MPa tensile, ≥35 J at 0 °C Charpy; mechanical properties are verified at 1/4-radius. 100 % UT to EN 10228-2 Class 3 and MT to ASTM E709 guarantee freedom from cracks; straightness ≤1 mm/m and dynamic balance to ISO 21940 G2.5 eliminate onboard vibration.   Features 360° forged fiber flow doubles fatigue strength versus welded assemblies; integral flame-hardened or induction-hardened journals reach 55 HRC with 8 mm case depth. Central 40 mm pilot bore reduces weight 12 % and allows condition-moni…