LTZC precision four-point contact slewing bearings have been successfully delivered in batches

Against the backdrop of continuous upgrading in the manufacturing of automated mechanical equipment, precision slewing bearings have become core components of automated equipment, construction machinery, robotic systems, and heavy-duty rotating platforms. LTZC, as a professional bearing supplier, recently completed a batch delivery of high-precision four-point contact slewing bearings to a German automation equipment manufacturer customer, and the bearings successfully passed customer acceptance and on-site operational testing. This not only demonstrates LTZC's manufacturing capabilities in the field of high-precision slewing bearings but also further consolidates its competitiveness in the global wholesale slewing ring market.

I. How Slewing Bearings Work？

A slewing bearing (or slewing ring) is a large rotating support capable of simultaneously bearing axial force, radial force, and overturning moment. This three-dimensional composite load capacity makes slewing rings an irreplaceable key component in equipment such as tower cranes, excavators, welding turntables, and port machinery. It features a large-diameter structure, a single row of balls forming four-point contact with the raceway, and 360-degree low-speed, heavy-load slewing capability.

1. Basic Structural Components of a Slewing Bearing

A typical slewing bearing mainly consists of the following parts:

Inner and outer rings (can have internal or external teeth)

Rolling elements (steel balls or rollers)

Cage or spacer

Sealing device

Lubrication system

Mounting holes

The slewing bearing is fixed to the equipment mounting surface through mounting holes. When the equipment rotates, the drive unit drives the inner or outer ring of the slewing bearing to rotate through the meshing of the gear ring, causing the rolling elements to roll between the raceways, thus achieving low-friction slewing motion.

II. What is a four-point contact ball slewing bearing?

Four-point contact slewing bearings are a type of single-row ball slewing bearing, and are commonly used in slewing bearings. Their raceways typically employ a two-segment symmetrical arc design, with the rolling elements forming four-point contact with the raceways, hence the name "four-point contact." Their design is simple and compact, lightweight, and low-cost, making them suitable for small to medium-sized excavators, cranes, and mechanical rotating joints.

Four-point contact ball slewing bearings typically include: toothless, external gear, and internal gear designs. LTZC, as a professional slewing bearing replacement solution provider, can provide equivalent replacement designs based on original equipment parameters and can also customize four-point contact ball slewing bearings according to customer needs.

III. Real-world Case Study: Mass Delivery of LTZC Four-Point Contact Ball Slewing Bearings

Project Background

A German automation equipment manufacturer had long been sourcing precision slewing bearings from overseas brands, but faced the following problems in the past two years:

Long delivery cycles (18-22 weeks)

Continuously rising costs

Slow response to customization modifications

Lagging after-sales support

The customer sought a bearing supplier capable of providing high-precision, customizable bearings with mass delivery capabilities, and supporting a wholesale slewing ring supply model. After multiple rounds of technical communication and sample testing, the customer ultimately selected LTZC as their core supplier.

Specific Parameters of Four-Point Contact Slewing Bearings

This batch of four-point contact slewing bearings adopts an external gear structure design. The main technical parameters are as follows:

Outer Diameter: 1280 mm

Inner Diameter: 980 mm

Material: 42CrMo (quenched and tempered)

Raceway Hardness: HRC 55-60

Hardened Layer Depth: ≥3mm

Axial Load Capacity: 850 kN

Overturning Moment Capacity: 1250 kN·m

Axial Runout Control: ≤0.05 mm

End Face Flatness: ≤0.08 mm

Contact LTZC for factory quote.

Technical Challenges Faced by the Customer

1. High Rotational Accuracy Requirements

The customer's equipment is used in an automated welding robot system, requiring extremely high repeatability. Radial runout or end face fluctuations in the slewing ring will directly affect weld quality.

2. Frequent Load Fluctuations

The equipment experiences frequent starts and stops during operation, resulting in constantly changing load directions. This poses a challenge to the raceway stress distribution of the four-point contact slewing bearings.

3. Service life requirement exceeds 20,000 hours. 

The customer's original supplier's products developed noise and increased gap issues after 12,000 hours.

IV. LTZC Four-Point Contact Ball Slewing Bearing Solution

1. Optimized Raceway Geometry

The LTZC engineering team optimized the raceway contact angle through finite element analysis (FEA), resulting in more uniform stress distribution on the steel balls and reducing edge stress concentration.

2. Precision Grinding Process

The raceway is CNC hardened and precision ground, with roundness controlled within 0.03mm. An online detection system ensures consistent precision.

3. Upgraded Heat Treatment

Segmented induction hardening technology is used to improve the uniformity of raceway hardness while avoiding internal stress concentration.

4. Improved Sealing and Lubrication

A unique double-lip seal is designed and filled with high-performance lithium-based grease. Secondary lubrication channels were included in the design drawings to account for future maintenance, effectively extending service life through both lubrication and sealing improvements.

Customer Feedback

After 6 months of operation following product installation, customer feedback is as follows:

Stable operation with no abnormal noise

Positioning accuracy improved by approximately 15%

Temperature rise was lower than the original brand's product

Procurement costs decreased by approximately 22%

Delivery time shortened to 8 weeks

The customer subsequently placed a second order, establishing a long-term partnership.

For slewing bearing solutions, please contact LTZC.

Conclusion 

The successful mass delivery of these precision four-point contact slewing bearings not only demonstrates LTZC's technological strength in the field of high-precision slewing bearings but also showcases its comprehensive competitiveness as a global professional bearing supplier.

In the future, LTZC will continue to deepen its slewing ring technology research and development, optimize the four-point contact structure design, and improve manufacturing precision and load-bearing capacity, providing global customers with more reliable slewing bearing replacement and wholesale slewing ring solutions.

If your equipment is seeking cost-effective, high-precision, and customizable slewing bearings, LTZC is a trustworthy long-term partner.