LTZC Heavy-Duty Slewing Bearings Pass Rotational Precision Testing

LTZC Heavy-Duty Slewing Bearings Pass Rotational Precision Testing 

I. China’s Specialized Supplier of Slewing Bearings — LTZC Bearings

As a domestic manufacturer specializing in the integrated R&D, production, and sales of heavy-duty slewing bearings, LTZC consistently upholds the core philosophy of "making our customers' rotation more precise." With over 30 years of deep expertise in the slewing bearing sector, we have served more than 50 countries and over 2,000 clients worldwide. We have accumulated extensive experience in both product application and technical R&D across diverse fields, including construction machinery, wind power, port operations, and mining. We maintain precise control over both product quality and production costs, offering factory-direct pricing and ensuring stable delivery.

Recently, LTZC successfully manufactured a large-scale, ultra-heavy-duty slewing bearing. Comprehensive rotational precision testing was subsequently conducted with the aim of rigorously validating the product's performance, thereby enabling us to provide reliable bearing solutions to our global partners.

II. Product Overview: Key Technical Parameters of the LTZC Heavy-Duty Slewing Bearing

The product undergoing rotational precision testing in this instance is a heavy-duty slewing bearing featuring three rows of cylindrical rollers, independently developed by LTZC. Classified as a large-diameter, high-load-capacity, and high-precision slewing ring, it is specifically engineered for heavy-duty machinery such as 4,000-ton class cranes, large-scale offshore wind installation vessels,and super-large port gantry cranes. Its key technical parameters are as follows:

Structural Type: Three-row cylindrical roller slewing bearing 

Outer Diameter: 4000 mm

Inner Diameter: 3200 mm

Height: 450 mm

Rated Dynamic Load: 12,500 kN

Rated Static Load: 48,000 kN

Material: High-quality alloy structural steel (42CrMo); raceway surface induction hardened + low-temperature tempered

Hardness: Raceway surface HRC 58–62; Core HRC 35–45

Precision Class: P4

Operating Temperature Range: -40°C to +80°C

Sealing Type: Multi-lip NBR rubber seals; dust and water protection rating: IP67

Design Life: ≥10,000 hours 

This product features a three-row cylindrical roller structural design, enabling it to simultaneously withstand radial loads, axial loads, and overturning moments; its load-bearing capacity is enhanced by over 30% compared to single-row bearings of the same diameter. The raceways undergo an ultra-precision grinding process, achieving a surface roughness of Ra ≤ 0.4 μm,which effectively reduces the friction coefficient and minimizes wear. Furthermore,it incorporates an innovative gradient heat treatment technology that resolves the challenge of heat-treatment deformation in large-diameter bearings, controlling the deformation rate to within 0.05% and ensuring overall precision stability.Designed to adapt to extreme operating conditions,it is capable of long-term, stable operation in environments characterized by high dust levels,high humidity, and strong corrosiveness, thereby meeting the rigorous operational demands of heavy-duty machinery.

Seeking Slewing Bearing Solutions

III. LTZC Extra-Heavy-Duty Bearing Testing Procedure

Step 1: Static Precision Inspection

Mount the bearing securely onto the test platform and align its center,ensuring that the installation coaxiality is ≤ 0.02 mm.

Manually and slowly rotate the bearing through a full 360 degrees;collect data on radial runout, axial runout, and face runout under static conditions. Repeat this measurement process five times and calculate the average values.

Utilize a roundness tester to measure the roundness and cylindricity errors of the raceways, and record the data.

Step 2: Dynamic Precision Inspection

Simulating actual operating conditions,apply 50% of the bearing's rated load. Inspect the bearing's rotational smoothness, observing for any issues such as sticking, abnormal noise, or speed fluctuations. Gradually increase the load to 100% of the rated load,and subsequently to a 120% overload condition; repeat the aforementioned inspection steps to verify the stability of precision under varying load levels.

Step 3: Temperature Adaptability and Precision Inspection

Using a temperature-controlled simulation system, sequentially adjust the test environment temperature to -40°C, 0°C, 25°C,60°C,and 80°C. Analyze the impact of these temperature variations on the bearing's rotational precision to verify the product's adaptability to different temperatures.

Step 4: Long-Term Operational Precision Stability Inspection

Apply 80% of the rated load and set the rotational speed to 2 r/min; allow the bearing to operate continuously for 100 hours.Upon completion of the operation, disassemble the bearing to inspect the raceways and rolling elements for signs of wear,thereby evaluating the stability of the bearing's precision over a prolonged period of operation.

IV. Conclusion of Precision Testing for LTZC Extra-Heavy-Duty Bearings

Precision Grade Compliance:The static and dynamic rotational precision of these heavy-duty slewing bearings fully meets the high-precision standards of ISO P4.Key runout indicators have been improved by over 60% compared to the industry-standard P5 grade,positioning the precision level of these bearings as leading domestically and advanced internationally.

Robust Load Adaptability:Within the rated load range of 50% to 120%, the rotational precision of the bearings exhibits no significant degradation;rotation remains smooth,free from jamming or abnormal noise,making them well-suited for the complex load conditions encountered in heavy-duty equipment.

Superior Thermal Stability:In extreme temperature environments ranging from -40°C to +80°C, fluctuations in all precision indicators remain within ≤15%. This demonstrates excellent thermal stability,satisfying operational requirements under extreme high- and low-temperature conditions.

High Long-Term Reliability:After 100 hours of continuous operation,the precision degradation rate was merely 7.4%. No significant wear was observed on the raceways or rolling elements,confirming the bearings' characteristics of long service life and high reliability.

V. LTZC Bearings — A Specialized Supplier of Slewing Bearings

Located in Luoyang, Henan, China, LTZC Bearings is a specialized manufacturer of slewing bearings that integrates R&D, production, sales, and service. The company focuses on the research, development, and manufacturing of heavy-duty, high-precision, and large-diameter slewing bearings. Its products are widely utilized across various sectors, including construction machinery, wind energy and new energy, port machinery, mining equipment, aerospace, and medical devices.

5.1 Independent Manufacturing Facility

The LTZC Bearings facility covers a total area of 10,000 square meters and employs over 300 staff members. The company possesses independent manufacturing capabilities covering the entire production chain—from heat treatment and precision machining to assembly and inspection—ensuring stable and reliable delivery. Equipped with multiple sets of CNC machine tools, the facility is fully capable of meeting the manufacturing requirements for large-diameter bearings.

5.2 Rigorous Quality Control

LTZC strictly adheres to the requirements of ISO 9001 (Quality Management), ISO 14001 (Environmental Management), and ISO 45001 (Occupational Health and Safety Management) certification systems. The company has established a comprehensive quality control system that encompasses every process, stage, and personnel member. All finished products undergo 100% comprehensive testing, and each unit is assigned a unique quality traceability code, enabling full-process traceability from raw materials to the final product.

5.3 Customized Bearing Solutions

LTZC Bearings provides customers with a one-stop, full-lifecycle service experience—covering pre-sales, in-sales, and after-sales stages. Services include free bearing selection assistance, customized bearing design solutions, and technical support to help customers resolve issues during installation and commissioning. Solutions are provided within 24 hours.

5.4 A Trusted Bearing Brand — LTZC Bearings

With 20 years of development, LTZC products have been exported to over 50 countries and regions worldwide, serving more than 2,000 clients across diverse sectors such as construction machinery, wind power, port operations, mining, and aerospace. The company has successfully established a brand image synonymous with high quality, high reliability, and exceptional cost-effectiveness in both domestic and international markets, earning widespread recognition and acclaim from customers.

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