How does slewing bearing work?

What is Slewing Bearing?
A slewing bearing (also known as a turntable bearing) is a large-scale bearing device capable of simultaneously bear axial forces, radial forces, and overturning moments. It is widely used in engineering machinery, wind power equipment, port machinery, military equipment, and other fields requiring rotational or slewing motion. Its core function is to connect the fixed and rotating parts of equipment, enabling high-precision, high-load-capacity smooth rotational movement.

Core Components: Typically consists of an inner ring, outer ring, rolling elements (steel balls or rollers), spacer blocks, sealing devices, and a lubrication system.

Classification: Divided into single-row four-point contact ball type, double-row different-diameter ball type, cross roller type, etc., based on structure, to meet diverse load and operational requirements.

Features of Slewing Bearings

High Load Capacity: Capable of bear combined axial, radial, and overturning moment loads, suitable for heavy-duty and high-impact conditions.

Compact Structure: Integrated design simplifies equipment structure and reduces installation space.

High Rotational Precision: Precision machining ensures smooth rotation, minimizing vibration and noise.

Longevity & Reliability: Utilizes high-quality steel (e.g., 42CrMo), surface hardening treatments (e.g., induction hardening), and integrates sealing and lubrication systems to withstand harsh environments.

Customization: Customizable in size, load capacity, gear rings (internal/external teeth), and mounting hole configurations based on client needs.

How Does Slewing Bearing Work?
A slewing bearing primarily comprises an inner ring, outer ring, rolling elements, and a cage. Its operational process is complex, detailed as follows:

Load Transmission

Radial Load Transmission: When radial loads act on the bearing (e.g., self-weight of rotating components or external horizontal forces), the inner ring tends to displace radially. The inner ring transfers this force to the rolling elements in contact, which undergo elastic deformation at contact points (similar to spring compression) to resist the radial force. The rolling elements then transmit the force to the outer ring, which transfers it to the fixed structure via its connection, achieving radial load bearing and transmission.

Axial Load Transmission: For axial loads (e.g., axial thrust or tension on rotating components), the inner ring transfers axial forces to the rolling elements. Contact points between the rolling elements and inner/outer raceways deform axially to bear and transmit axial forces. Due to the shape and contact angle design of the rolling elements, axial forces are efficiently transferred from the inner ring to the outer ring and then to the fixed structure.

Overturning Moment Transmission: When bear overturning moments (e.g., moments generated by eccentric loads during crane arm rotation), the inner and outer rings experience uneven loads at different positions. Rolling elements on one side bear higher pressure, while those on the opposite side bear lower pressure. Through variations in contact force distribution and elastic deformation of the rolling elements, overturning moments are converted into complex stress distributions among the inner/outer rings and rolling elements, enabling stable support for rotating components.

Rotational Motion Realization

Rolling Element Movement: When the inner or outer ring is driven by external force, the rolling elements roll within the raceways. Contact between rolling elements and raceways is point- or line-based, with extremely low friction coefficients, allowing smooth rolling. The rolling speed correlates with the rotational speeds of the inner/outer rings, enabling relative motion between them.

Role of the Cage: The cage evenly spaces rolling elements, preventing collisions or crowding. It also guides their movement within the raceways, ensuring accurate trajectories and avoiding misalignment or detachment. Cage design and material selection prioritize stability and wear resistance under high-speed rotation and load conditions.

Precision Maintenance & Lubrication: High machining precision and surface quality of the inner/outer rings and rolling elements are critical to maintaining rotational accuracy. Minor dimensional deviations or surface defects may cause vibration, noise, or accelerated wear. Proper lubrication is essential: grease or oil forms a film between rolling elements and raceways, reducing friction and wear while cooling and preventing corrosion, thereby extending service life.

 Supplier of Slewing Bearings

LTZC Corporation is a national high-tech enterprise specializing in the R&D, production, and service of core components for high-end equipment. With over a decade of expertise in the machinery manufacturing industry, we are driven by technological innovation and committed to providing global clients with high-precision, highly reliable industrial transmission solutions. The company boasts an internationally leading R&D team and intelligent production bases. Our products are certified by the ISO 9001 Quality Management System and meet multiple international standards, serving clients across more than 30 countries and regions worldwide.

Core Business Areas
LTZC focuses on engineering machinery, renewable energy equipment (wind/solar power), port heavy-duty machinery, mining equipment, and special-purpose vehicles. We deliver customized transmission system designs and core component integration services. By deeply understanding industry challenges, we continuously optimize product performance to enhance equipment efficiency and longevity for our clients.

Flagship Product: Slewing Bearings
As a testament to our technical prowess, LTZC slewing bearings stand as an industry benchmark for outstanding quality:

Precision Customization: Supports non-standard designs, covering full-series structures such as single-row ball and cross roller types, compatible with megawatt-level wind turbine towers, tunnel boring machines, cranes, and other heavy-duty equipment.

Extended Durability: Utilizes carburizing and quenching processes paired with precision grinding technology, increasing bearing service life by over 40%.

Rigorous Quality Control: Each product undergoes 12 inspection procedures including 3D contour scanning and ultrasonic flaw detection, maintaining a failure rate below 0.2%.

Rapid Response: Leverages a digital supply chain to provide full-cycle service support from design to after-sales maintenance.
Guided by our mission of "Precision Transmission, Intelligent Manufacturing for the Future," LTZC continues to pioneer slewing bearing technology innovations, empowering global industrial equipment upgrades. For product details or customized solutions, please contact our expert team—we are ready to deliver optimal solutions tailored to your needs!