Overview
Single-Row Four-Point Contact Ball Slewing Bearings are compact, high-performance rotational components designed to handle combined loads with exceptional efficiency.
These bearings feature a unique design where each ball makes four contact points with the raceways, enabling them to simultaneously accommodate axial, radial, and moment loads from multiple directions.
View Our Factory Products
Structural Composition
- Outer Ring – The stationary component with precision-machined raceways
- Inner Ring – The rotating element with matching raceways
- Balls – High-grade steel balls that transmit forces between rings
- Separators – Maintain precise ball spacing and prevent contact
- Sealing System – Protects against contaminants and retains lubrication
- Mounting Holes – For secure installation to machinery
Four-Point Contact Principle
The defining characteristic of these bearings is the special “gothic arch” raceway geometry that creates four distinct contact points between each ball and the raceways:
- Two contact points with the outer ring raceway
- Two contact points with the inner ring raceway
This innovative design provides exceptional load distribution and enables the bearing to handle complex loading conditions with a compact single-row configuration.
Load Capacity
Single-row four-point contact ball slewing bearings are engineered to handle three types of loads simultaneously:
- Axial Loads – Forces parallel to the rotation axis
- Radial Loads – Forces perpendicular to the rotation axis
- Moment Loads (Overturning Moments) – Tilting forces that create rotational torque
This combined load capacity makes them ideal for applications requiring compact designs with multi-directional loading.
Performance Advantages
- Compact cross-section
- Low rotational torque
- High rotational accuracy
- Cost-effective solution
- Easy installation
Gear Configuration Options
Non-Geared Type
- Simplest configuration
- Direct drive applications
- Minimal maintenance requirements
- Most cost-effective solution
- Compact design with minimal protrusions
Internal Gear Type
- Gear teeth cut on inner ring bore
- Protected gear location
- Reduced contamination risk
- Compact external dimensions
- Preferred for space-constrained applications
External Gear Type
- Gear teeth cut on outer ring circumference
- Easier maintenance access
- Higher torque transmission capacity
- Simpler lubrication access
- Wider pinion gear selection
Typical Applications
Construction Machinery
- Small to medium-sized excavators
- Mobile cranes (up to 50-ton capacity)
- Concrete pump trucks
- Aerial work platforms
- Compact loaders
Industrial Equipment
- Material handling turntables
- Packaging machinery rotators
- Welding positioners
- Indexing tables
- Light-duty wind turbine yaw systems
Selection Considerations
| Factor | Consideration | Recommendation |
|---|---|---|
| Load Capacity | Axial, radial and moment loads | Calculate all load components including dynamic factors |
| Gear Type | Non-geared, internal or external gear | Determine based on drive system requirements and space constraints |
| Mounting | Surface flatness and stiffness | Ensure mounting surfaces meet ISO standard tolerances |
| Operating Environment | Temperature, contaminants, corrosion | Select appropriate seals and lubrication |
| Rotational Speed | RPM requirements | Consider centrifugal forces at high speeds |
Maintenance Recommendations
- Regular lubrication intervals based on operating conditions
- Periodic inspection of seals for damage or wear
- Check for abnormal noise or vibration during operation
- Monitor gear teeth for proper meshing and wear patterns
- Keep mounting surfaces clean and properly torqued
Technical Specifications
Standard Sizing
- Bore diameters: 100mm to 2000mm
- Axial load capacity: 5kN to 1500kN
- Radial load capacity: 3kN to 800kN
- Moment capacity: 10kN·m to 1500kN·m
Material Specifications
- Rings: 42CrMo/50Mn alloy steel
- Balls: GCr15 bearing steel (HRC 60-65)
- Separators: Nylon 6/6 or brass
- Seals: NBR rubber with steel reinforcement