Digger Slew Ring

Digger Slew Ring – Heavy-Duty Slewing Bearing for Excavators

At Luoyang Hengguan Bearing Technology, we produce precision-engineered digger slew ring solutions designed for harsh excavation conditions. Our Slewing Bearings feature three-row roller or double-row ball structures, with bore diameters ranging from Ø200mm to Ø2000mm, suitable for excavators from 1 ton to over 50 tons. Each product undergoes induction hardening to achieve a raceway surface hardness of 55-62 HRC, while maintaining core toughness for excellent shock resistance. With over 20 years of professional experience and ISO 9001 certification, our engineering team delivers load-bearing components that withstand axial, radial and tilting moment forces during continuous 360-degree rotation. We supply customers across more than 50 countries with robust, field-proven turntable bearing technology.

Digger Slew Ring Details

Your excavator requires a reliable slewing bearing that will not fail under heavy loads. Our product acts as the core rotational connection between the undercarriage and upper structure. It is more than just a standard bearing — it is a key component that ensures stable full-bucket swing stops without excessive machine vibration.

These bearings are manufactured with high-quality 50Mn or 42CrMo alloy steel rings, paired with GCr15 precision rolling elements. The raceway surfaces adopt medium-frequency induction hardening treatment, forming a wear-resistant outer layer while retaining a tough, impact-resistant core. This dual-hardness design effectively prevents surface wear and unexpected ring cracking under shock loads caused by hydraulic breakers and rock buckets.

Every unit is equipped with precision-machined external or internal Gearing. Advanced CNC gear shapers and grinding equipment ensure accurate and consistent tooth profiles, enabling smooth rotation and reducing pinion motor load during operation.

Why Choose Us

Diameter Range Adaptability: We supply slewing bearings with outer diameters from 50mm to 10,000mm, covering mini excavators to large mining equipment.Four-Level Precision Options: Choose from P0, P6, P5 and P4 precision grades to meet your rotational accuracy requirements.

Custom Engineering Capability: Our team provides professional consultation, 3D design support, and reverse engineering services for obsolete models, with no original drawings required.

Proven Industry Experience: Partners from Germany, Australia, South Africa and the United States already rely on our components. We comply with international logistics and technical documentation standards.

Production Depth: Equipped with in-house CNC vertical lathes, hardening machines and large gear hobbing equipment, we control quality at every manufacturing stage instead of outsourcing critical processes.

Technical Specifications

Features and Benefits

Mid-Frequency Induction Hardening: The raceway surface reaches 55–62 HRC with uniform depth penetration. This process greatly extends service life in harsh conditions, while the tougher core absorbs impact energy during sudden load reversals.

Precision Gear Integration: CNC-machined teeth undergo grinding and heat treatment to achieve high profile accuracy. It delivers smoother rotation, lower noise levels, and reduced maintenance for your slewing drive system.

Advanced NBR Sealing: Oil-resistant NBR seals prevent lubricant leakage and block contaminant ingress. This is critical for dusty quarries and wet crushing sites, where seal failure commonly leads to premature bearing damage.

Material Selection Rationale: We adopt 50Mn for standard working conditions and 42CrMo for heavy-duty mining excavators that demand maximum core toughness under hydraulic breaker impact loads.

Anti-Corrosion Treatment: Phosphate coating and anti-rust oil treatment extend outdoor storage life and protect components in marine and high-humidity environments.

Applications

Hydraulic Excavators: Our excavator slew rings support crawler and wheeled excavators across all weight classes. Whether operating a 1.5-ton mini excavator for urban utility work or a 50-ton mining machine, the bearing withstands full static loads and dynamic forces generated by bucket filling and swing braking.

Crawler Cranes: These machines generate extreme tilting moments during load lifting at maximum boom extension. The slewing bearing manages eccentric weight distribution and prevents dangerous upper structure tilting.

Rotary Drilling Rigs: Continuous rotation under high downward thrust creates unique bearing stress conditions. Our three-row roller designs distribute these forces across multiple load paths.

Demolition & Forestry Equipment: Grapples and shears produce fluctuating moment loads while operators handle irregular materials. The bearing stabilizes the upper structure during rapid directional changes.

Marine & Amphibious Operations: Dredging and waterfront excavators require enhanced sealing and corrosion resistance. We provide customized surface treatments for components exposed to submersion and saltwater

Installation Guide

Pre-Installation Inspection: Verify mounting surface levelness on both the undercarriage and upper frame. Surface irregularities directly create bearing stress concentrations.

Bolt Tightening Sequence: Use a star pattern when torquing mounting bolts. This distributes clamping force evenly and prevents ring distortion.

Lubrication Point Access: Ensure all grease nipples remain accessible after installation. Blocked lubrication points are a leading cause of premature bearing failure.

Gear Mesh Adjustment: Check pinion-to-ring gear backlash in accordance with the original equipment manufacturer’s specifications. Excessive backlash causes impact loading, while insufficient clearance generates excessive heat.

Seal Orientation: Install seals with the lip facing inward to retain lubricant. Reversed seals will cause immediate grease leakage.

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

Our facility maintains ISO 9001 quality management certification. Every production batch undergoes dimensional verification using coordinate measuring machines to confirm raceway geometry and gear tooth accuracy.

We perform rotational torque testing to validate smooth operation across the full 360-degree range. Hardness testing confirms raceway treatment effectiveness before final assembly.

All products comply with ISO and DIN bearing standards. Our components meet RoHS requirements for environmentally responsible manufacturing.

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).

Maintenance and Care

Lubrication Schedule: Apply calcium-based or lithium-based grease every 100 operating hours, or weekly in dusty environments. Insufficient lubrication accounts for 70% of slewing bearing failures we analyze.

Bolt Torque Verification: Re-check mounting bolt tightness after the first 50 hours of operation, then quarterly. Loose bolts create fretting wear on mounting surfaces.

Seal Condition Monitoring: Inspect seals monthly for cracks, displacement, or hardening. Replace immediately if you notice grease leakage or contamination ingress.

Raceway Condition Assessment: During major service intervals, rotate the bearing through its full range while monitoring for roughness, grinding noises, or resistance changes that indicate wear progression.

Storage Practices: If storing a spare bearing, keep it horizontally on a flat surface in a dry environment. Coat exposed surfaces with anti-rust oil and rotate quarterly to prevent lubricant settling.

FAQ

Q: What's the difference between three-row roller and double-row ball designs?

A: Three-row roller bearings handle higher load capacity, making them suitable for excavators above 20 tons. Double-row ball designs offer lower friction for smaller machines where weight and swing speed matter more than maximum load rating.

Q: Can you manufacture a replacement bearing without original drawings?

A: Yes. We provide reverse engineering services. Send us your old bearing or critical dimensions, and our team will create a compatible replacement design including gear specifications.

Q: How do I know which precision class I need?

A: P0 grade suits standard construction excavators. Specify P6 or P5 for machines requiring tighter rotational accuracy, such as precision demolition equipment. P4 is reserved for specialized applications with strict wobble tolerances.

Q: What causes the "clunking" sound during swing operation?

A: This typically indicates excessive gear backlash or worn rolling elements. Check your pinion-to-ring gear clearance first, then assess bearing internal clearance if gear adjustment doesn't resolve the issue.

Q: Do your bearings come pre-greased?

A: We apply a preservation coating for shipping. You must fully pack the bearing with appropriate grease during installation according to your equipment manufacturer's specifications.

Q: What's your typical production lead time?

A: Standard sizes ship within 2-3 weeks from stock. Custom-engineered units require 6-8 weeks depending on diameter and complexity. Contact Us with your specifications for an accurate timeline.

Contact Us

Need technical specifications or a custom bearing solution? Our engineering digger slew ring's team is ready to support your project. Reach out to us at mia@hgb-bearing.com for expert consultation.