Precision Meets Performance: A Deep Dive into Four Point Contact Ball Slewing Bearings
What is a Four Point Contact Ball Slewing Bearing?
A Four Point Contact Ball Slewing Bearing is a type of rotational rolling-element bearing that allows one row of balls to contact the raceway at four points. This unique geometry enables the bearing to carry axial loads in both directions, radial loads, and tilting moments—simultaneously. Because of its compact structure and ability to handle complex combined loads, this bearing is widely used in applications that demand high reliability, space efficiency, and operational precision.

The Engineering Behind Four Point Contact Bearings
At the heart of a four-point contact slewing bearing lies its cross-section geometry. The inner and outer rings are typically split into two halves, and the raceways are designed to enable contact at four distinct points. The contact angle is generally 35°, which allows the balls to bear force both axially and radially.
The internal clearance is carefully optimized during design to accommodate misalignment and thermal expansion, while maintaining high rotational accuracy. LDB Bearing uses advanced CNC machining and induction hardening processes to produce precision-ground raceways, which significantly extend the bearing’s service life under dynamic load conditions.
Key Structural Advantages
Simplified design: One bearing does the job of two.
Weight saving: Reduces overall system mass, especially in rotating equipment.
Fewer parts: Lowers assembly complexity and maintenance costs.
High stiffness: Offers excellent support under eccentric or offset loads.
Typical Applications of Four Point Contact Ball Slewing Bearings
This bearing style is a favorite in industries where multifunctional load handling and space constraints are critical. Below are some representative application domains where LDB’s four-point bearings perform exceptionally well:
Construction Machinery
Crawler cranes, truck-mounted cranes, and excavators all depend on four point contact bearings to support boom rotation and lifting. These bearings must support significant radial loads from the rotating superstructure and moment loads due to heavy lifting. LDB supplies high-load-capacity models to construction OEMs worldwide.
Wind Energy
Yaw bearings in wind turbines allow the nacelle to rotate and face the wind. These bearings endure frequent wind direction changes and high axial loads. LDB offers anti-corrosion treated models and customized seal configurations for offshore and onshore applications.
Medical Imaging Equipment
In large diagnostic machines like CT scanners and radiotherapy devices, bearings must deliver smooth, quiet, and stable rotation. LDB produces precision-ground models with ultra-low noise and minimal backlash to meet the strict requirements of the medical field.
Industrial Turntables and Robots
Rotary tables and robotic joints benefit from the compact design and precision of four-point contact bearings. LDB’s product range supports automated welding stations, assembly arms, and semiconductor inspection equipment.
Aerial Platforms and Lifts
Stability and safety are paramount in elevating work platforms. LDB bearings ensure safe load support and smooth motion across varying elevation and rotation conditions.
LDB’s Four Point Contact Slewing Bearing Portfolio
LDB Bearing, headquartered in Luoyang, China, is a globally recognized manufacturer specializing in slewing rings and drive solutions. Their four point contact ball slewing bearings are manufactured under ISO 9001 and ISO/TS 16949-certified quality systems.
Product Features:
Materials: Forged 42CrMo or 50Mn rings with GCr15 steel balls.
Hardness: Raceway hardness 55–62 HRC for long wear life.
Raceway Design: Precision-ground for uniform ball contact.
Customization: Inner ring, outer ring, or gearless options available.
Diameter Range: 300 mm to 10,000 mm to fit light to heavy machinery.
LDB also offers tailored solutions with specific bolt patterns, grease nipples, sealing systems, and pre-load settings based on customer drawings or industry standards.
Pricing Overview
Pricing for four point contact ball slewing bearings depends on a range of factors including:
Bearing size and gear type (external/internal/no gear)
Material grade and surface treatment
Load rating and dynamic requirements
Custom features (seals, mounting holes, lubrication)
As a rough estimate, small- to mid-sized models (300–1000 mm OD) range from $300 to $1200 USD per unit, while large-scale models (2000+ mm OD) can cost upwards of $5000 USD. LDB offers volume discounts for OEM clients and long-term project partnerships.
To obtain accurate pricing, customers can submit inquiries through LDB’s official website or consult directly with a sales engineer for a personalized quote.
Why Choose LDB?
LDB Bearing has over 20 years of manufacturing experience in large-diameter bearing production. Here’s why global clients choose LDB as their go-to slewing bearing supplier:
Advanced Production Capabilities
Over 300 CNC machining centers
Induction hardening, gear shaping, and ultrasonic testing
Integrated QC processes with 100% inspection before delivery
Technical Support & Engineering
2D/3D CAD support for design validation
Finite element analysis (FEA) to ensure load safety
Application-specific customization (robotics, energy, medical, etc.)
Worldwide Distribution
LDB’s products are exported to over 40 countries and regions including Europe, Southeast Asia, North America, and the Middle East. The company supports global clients with bilingual technical documentation and 24/7 after-sales service.
Conclusion
Whether you’re designing a crane, building a wind turbine, or innovating in automation, the four point contact ball slewing bearing is an engineering solution that combines strength, compactness, and reliability. Backed by precision manufacturing and deep application knowledge, LDB Bearing delivers world-class solutions that meet and exceed industry standards.
For a future-proof investment in bearing performance, choose LDB—where quality meets innovation.