Double-Row Slewing Ring

Double-Row Slewing Ring: High-Capacity Rotary Bearing Solution

Luoyang Heng Guan Bearing Technology offers precision-engineered double-row slewing ring solutions designed for demanding industrial applications. With over 20 years of manufacturing  Experience, our team of 50+ specialized engineers produces Slewing Bearings ranging from 50 mm to 10,000 mm in diameter, with precision grades covering P0, P6, P5, and P4.

Our design features two vertically arranged raceways that simultaneously handle axial loads, radial forces, and tilting moments, with cross-section heights up to 100 mm. Manufactured from high-strength 50Mn or 42CrMo alloy steel with GCr15 steel balls, these rings undergo rigorous heat treatment to achieve 55-62 HRC raceway hardness. ISO 9001 certified and RoHS compliant, our products are exported to over 50 countries across Europe, North America, and the Asia-Pacific region.

Double-Row Slewing Ring Details

Our double-row slewing ring features two rows of steel balls in a back-to-back arrangement within precision-machined raceways. This dual-raceway structure distributes loads more evenly than single-row designs, significantly improving equipment stability under combined loading conditions.

The ring body utilizes high-grade 42CrMo or 50Mn structural steel, undergoing quenching and tempering to achieve a core toughness of 229-269 HBW. Critical raceway surfaces receive induction hardening (55-62 HRC), ensuring excellent resistance to contact fatigue and surface spalling during continuous operation.

Our manufacturing process employs CNC vertical lathes for precision turning, CNC hardening machines for controlled heat treatment, and CNC Gear shapers for accurate mounting hole positioning. Each bearing undergoes dimensional verification using Coordinate Measuring Machines (CMM) to ensure tolerances meet your assembly requirements.

Standard sealing uses oil-resistant Nitrile Rubber (NBR) strips to protect against dust ingress and grease leakage in harsh environments. Mounting holes follow standard bolt patterns, with custom flange interfaces available based on your 3D drawings or legacy product mapping.

Why Choose Us

You gain access to two decades of slewing bearing expertise based in Luoyang, the hub of China’s bearing industry. Our 50-member engineering team focuses exclusively on the design and production of high-performance rotational components.

We maintain full in-house manufacturing capabilities. Your order is processed through our CNC vertical lathes, heat treatment furnaces, gear hobbing machines, and precision grinding equipment—ensuring zero outsourcing of critical processes. This vertical integration guarantees consistent quality and reliable delivery timelines.

Your specific requirements get personalized attention. Whether you need non-standard dimensions, unique mounting configurations, or specialized materials, our team provides technical consultation and custom designs based on your actual working conditions. We also support reverse engineering when original drawings are unavailable. Simply send us a worn bearing, and our team will map the specifications for replacement manufacturing.

Our production capacity scales with your project. We handle everything from single prototypes for testing to high-volume production runs, while maintaining stock of standard models for rapid shipment.

Technical Specifications

​​​​​​​Features and Benefits

Optimized Load Distribution: Two rows of steel balls provide a larger contact area than single-row designs. This achieves 40-60% higher load capacity without increasing the outer diameter—essential when mounting space is limited.

Superior Tilting Resistance: The back-to-back ball arrangement creates a wider effective load spread. Your equipment resists overturning moments during off-center loading or sudden lateral forces, reducing structural failure risks in crane applications.

Lower Friction Coefficient: Ball contact generates less rolling resistance than cylindrical or tapered rollers. You benefit from smoother rotation at higher speeds, with lower drive motor requirements and reduced energy consumption.

Compact Cross-Section: Optimized raceway geometry delivers high moment rigidity within minimal radial space. This provides design flexibility where envelope dimensions are restricted but structural stiffness is critical.

Enhanced Sealing: Multi-lip NBR seals prevent contamination ingress while retaining grease. This extends maintenance intervals in dusty mining environments or corrosive marine applications.

Manufacturing Precision: CNC machining maintains raceway roundness and surface finish to P4 tolerances. Your assembly achieves smooth rotation without the vibration or noise that accelerates wear.

Applications

Heavy-Duty Tower Cranes: Your cranes handle high tilting moments during high-altitude lifting. The double-row slewing ring provides a stable base under variable wind loads and off-center hook positions—essential for job site safety.

Port and Marine Cranes: Maritime environments demand robust sealing and corrosion resistance. Our bearings ensure continuous operation in high-humidity conditions during heavy-load container handling and ship-to-shore transfers.

Material Handling Stackers: Mining and logistics equipment requires reliable rotation under constant vibration and dust exposure. Your boom arms and reclaimer tools benefit from extended service life with minimal maintenance downtime.

Industrial Robots: Precision positioning systems require smooth, low-friction rotation. You achieve repeatable accuracy in automated welding and material handling applications where cycle time directly impacts productivity.

Medical Equipment: CT scanners and radiation therapy machines require vibration-free rotation. Our bearings deliver consistent image quality through precision-ground raceways and balanced rolling elements.

Installation Guide​​​​​​​

Clean all mounting surfaces to remove dirt, rust, or old lubricant. Verify that flange flatness meets your bearing specification to prevent distortion during bolt tightening.

Position the bearing carefully using lifting equipment. Align mounting holes before inserting bolts to avoid cross-threading or hole damage.

Install bolts following star pattern tightening sequence. Use calibrated torque wrench to achieve specified preload, preventing uneven clamping that causes raceway deformation.

Verify rotation smoothness by hand before connecting drive systems. Binding or tight spots indicate misalignment requiring correction before operation.

Inject recommended lubricant type and quantity through grease fittings. Rotate bearing several revolutions to distribute lubricant evenly across raceways.

Check mounting bolt torque after initial 50 operating hours. Thermal cycling and vibration may require retightening to maintain proper preload.

Exhibition

We attend many famous international exhibitions such as Shanghai International Maritime Exhibition,Mining World Russia, bauma China, CTT Russia, etc

Partners

Your trust, we cherish in heart all times and will reciprocate that trust with unwavering quality.

Testing & Certification

Your bearing undergoes comprehensive quality verification before shipment. Coordinate measuring machines verify dimensional accuracy across critical parameters including bore diameter, raceway geometry, and mounting hole positions.

Vibration testing equipment measures rotational smoothness to detect raceway defects or rolling element inconsistencies that could cause premature failure. We record baseline vibration signatures for your reference during installation and operation.

Material certificates follow EN 10204 3.1 standards, providing full traceability from steel mill to finished product. Heat treatment depth (Eht) verification confirms hardening penetration meets design specifications for your load requirements.

Our ISO 9001 certification covers design, manufacturing, and inspection processes. RoHS compliance ensures your products meet environmental regulations in European and North American markets.

Maintenance and Care

Inspect seals monthly for damage or wear that allows contamination entry. Replace damaged seals immediately to prevent raceway contamination and accelerated wear.

Lubricate according to operating conditions. Heavy loads or continuous operation require more frequent greasing than intermittent or light-duty applications. Monitor grease condition during routine inspections.

Monitor mounting bolt torque quarterly. Vibration and thermal expansion may loosen fasteners, reducing clamping force and allowing fretting corrosion between mating surfaces.

Check for abnormal noise or vibration during operation. Unusual sounds indicate potential raceway damage, contamination, or inadequate lubrication requiring immediate investigation.

Record operating hours and maintenance activities. Trend analysis helps predict bearing life and schedule replacement before unexpected failure causes production downtime.

Packaging & shipping

Your goods are unique, and their journey should be flawless. Therefore, we offer professional and customized packaging services. Our experienced team will evaluate your goods' characteristics, transportation route, and environmental requirements to recommend the most secure solution, such as: wooden crate packaging, sturdy frame packaging, or composite reinforced packaging (wooden crate + iron frame).

Positive customer reviews

Our quality and service have received widespread praise from our customers.

FAQ

Q: What diameter range do you manufacture?

A: We produce from 50 mm to 10,000 mm inner bore diameter with various cross-section heights to match your load requirements.

Q: Can you customize mounting hole patterns?

A: Yes, we manufacture custom bolt configurations based on your flange specifications or provide mapping services for legacy equipment without drawings.

Q: What precision grades are available?

A: We offer P0, P6, P5, and P4 precision grades following ISO standards to meet your accuracy requirements.

Q: How long does custom manufacturing take?

A: Production time depends on size and complexity. Standard modifications require 4-6 weeks; complex custom designs may need 8-10 weeks.

Q: Do you provide installation support?

A: Our engineering team offers technical consultation and installation guidance to ensure proper mounting and optimal performance.

Q: What is the typical service life?

A: Service life varies with load conditions and maintenance practices. Properly maintained bearings in appropriate applications typically exceed 20,000 operating hours.

Contact Us

Ready to discuss your double-row slewing ring requirements? Our engineering team provides technical consultation and custom solutions for your specific application. Contact Us at mia@hgb-bearing.com for quotations and technical support.