Hot-forged Roller Step Shaft

Product Description Roller step shafts integrate multiple diameters on one forged bar to support bearing races, seal sleeves and roller shells. Open-die forging from vacuum-degassed alloy steels (4130, 42CrMo4, 34CrNiMo6, A182 F53) produces blanks Ø 80–1 200 mm, length ≤ 12 m, weight ≤ 25 t. Multi-stage upsetting and cross-wedge rolling form steps in one heat, keeping fibre flow continuous around every fillet.     Performance Quench-temper delivers 550–1 100 MPa UTS, 450–950 MPa yield, ≥ 25 J at –60 °C; journals can be induction-hardened to 55 HRC with 6 mm case. Journal surface finish 0.16–0.63 µm and run-out ≤ 0.02 mm eliminate vibration and extend bearing life. 100 % UT EN 10228-3 and MT ASTM E709 guarantee defect-free critical sections.   Features As-forged machining allowance 3–6 mm per step reduces cutting time 30 %; integral forged flanges, keyways and center-gun drilled pilot hole remove welds and balance weights. Full 3.1/3.2 certification and ABS/DNV/BV approval available.…