Marine slewing support ring forging

Product Description Marine slewing support ring forgings are seamless, hot-rolled and CNC-finished rings that serve as the structural core of deck cranes, platform jib hoists and shipboard gantry slew bearings. Starting from vacuum-degreased 42CrMo, 50Mn or duplex stainless billets, we forge, upset and ring-roll blanks 500–4 000 mm OD, 60–600 mm wall, up to 12 t unit weight. Pre-machining includes inner/outer raceways, gear cutting (straight or helical) and bolt-hole patterns to ABS/DNV client drawings; final hardness is 229–269 HB base material with 55–62 HRC induction-hardened raceways.     Performance Quench-temper plus raceway induction hardening yields 700 MPa yield, 900 MPa tensile, ≥42 J average at –20 °C (single ≥27 J) Charpy; values meet DNVGL-OS-E101 and API 2C. Rings survive 50 000 slew cycles under 1.25 × static limit moment; salt-spray test 1 000 h per ASTM B117 shows ≤0.02 mm corrosion loss. 100 % UT to EN 10228-3 Class 3, MT to ASTM E709, and 3.2 certificates issued…