Large Size Bearings (LSB) – 380+ mm Outer Diameter are heavy-duty rolling bearings engineered for massive industrial equipment where standard bearing sizes are insufficient. With outer diameters exceeding 380 mm and reaching up to several meters, these bearings support extraordinary loads while maintaining precise rotational performance in the world's largest machinery.
Key Technical Features:
Size range: Outer diameters from 380 mm to over 2,000 mm, with corresponding bore diameters typically ranging from 200 mm to 1,500 mm or larger. Bearing widths scale proportionally, often exceeding 100 mm for heavy load capacity.
Load capacity: Engineered for extreme radial and axial loads, often exceeding 500 kN dynamic load rating and multi-meganewton static ratings. Multi-row roller configurations (cylindrical, tapered, or spherical) maximize load distribution.
Configurations available:
Large DGBB: Deep groove ball bearings for moderate loads and higher speeds.
Large CRB: Cylindrical roller bearings for highest radial load capacity.
Large TRB: Tapered roller bearings for combined radial and thrust loads.
Large SRB: Spherical roller bearings for misalignment accommodation.
Four-point contact ball bearings: For combined loads with compact axial dimensions.
Slewing rings: With or without integral gearing for rotational positioning.
Materials: Through-hardened or case-carburized bearing steel (52100, 4320, or equivalent) with specialized heat treatment for large-section components. Nitriding or induction hardening for raceway surfaces.
Precision classes: Available in P0 (standard), P6, or P5 depending on application requirements. Special tolerances for wind turbine or aerospace applications.
Internal design: Optimized roller profiles (crowned or logarithmic) prevent edge stresses under heavy loads and misalignment. Controlled internal clearance (C3, C4, or custom) accommodates thermal expansion and housing deformation.
Cage options: Machined brass, steel, or polymer cages designed for dimensional stability in large diameters. Full-complement designs available for maximum load capacity.
Sealing systems: Heavy-duty labyrinth seals, multi-lip contact seals, or customized sealing solutions for contamination-prone environments.
Lubrication: Grease lubrication with relubrication channels and fittings; oil circulation systems for high-speed or continuous operation.
Applications:
Large size bearings (380+ mm OD) are essential in wind turbines (main shafts, yaw, and pitch drives), tunnel boring machines (TBMs), mining shovels and crushers, steel mill rolling mills, heavy-duty cranes, large excavators, offshore drilling equipment, radar and antenna systems, and paper mill drying cylinders. These bearings deliver reliable, long-life performance in critical, high-value capital equipment where bearing failure results in catastrophic downtime.
