Gearless Slewing Bearings for PV Tracking Systems | LTZC Bearings

1. What is a gearless slewing bearing?

The gearless slewing bearing is a key category of slewing bearings. Unlike external-gear or internal-gear variants, it features a smooth, gearless ring structure. Composed primarily of inner and outer rings, rolling elements, spacers, seals, and mounting bolts, it is a large-scale, precision mechanical bearing capable of simultaneously withstanding axial loads, radial loads, and tilting moments.

Its core operating principle aligns perfectly with the operational logic of photovoltaic (PV) tracking equipment: the circulation of internal precision rolling elements enables low-speed, high-frequency, and precise angular micro-adjustments of the PV mounting structure. Eliminating the need for gear-mesh transmission, it relies on a compatible drive unit to achieve flexible 360° rotation and precise positioning—perfectly meeting the requirement for PV panels to track the sun's trajectory in real-time.

In PV tracking system applications, mounting structures must undergo dozens of angular adjustments daily while operating in harsh outdoor environments characterized by wind, sand, high temperatures, heavy rain, extreme cold, and high humidity. With its minimalist structure and stable performance, the LTZC gearless slewing bearing is ideally suited for PV tracking systems.

II. Core Advantages of LTZC Gearless Slewing Bearings

2.1 Gearless Slewing Bearing Structure

Photovoltaic (PV) power plants are often located in harsh environments—such as deserts, coastal areas, and mountainous regions—where maintenance is difficult and costly. LTZC gearless slewing bearings feature a streamlined structure free of vulnerable gear components. They offer significantly extended lubrication intervals and enable long-term, maintenance-free operation, thereby drastically reducing the full-lifecycle O&M costs of PV power plants.

2.2 High-Precision Slewing Control

The core value of a PV tracking system lies in precise solar tracking, and bearing rotation accuracy directly determines tracking performance. LTZC gearless slewing bearings utilize precision grinding for raceways, maintaining accuracy within ±0.01 mm. With minimal rotational clearance and zero transmission backlash, they enable precise angular micro-adjustments at the 0.1° level, allowing PV panels to maintain the optimal angle for sunlight exposure and maximizing power generation efficiency.

2.3 Superior Weather and Corrosion Resistance

Designed to withstand operating conditions characterized by extreme temperature fluctuations, high corrosivity, and strong impacts, LTZC bearings are made from high-strength alloy structural steel. They undergo comprehensive heat treatment (quenching and tempering) and feature anti-corrosion surface treatments—such as hot-dip galvanizing or black oxide coating—to ensure adaptability to complex environments. The sealing system employs a dual-layer, wear-resistant, and waterproof structure that effectively blocks the ingress of wind-blown sand, rain, salt spray, and moisture.

2.4 High Load Capacity and Rigidity

LTZC gearless slewing bearings utilize a four-point contact ball design, enabling them to simultaneously withstand massive axial loads, radial loads, and tilting moments. With exceptional overall rigidity and load-bearing performance, they effectively resist external forces such as strong winds and heavy snow, preventing issues like bearing deformation, misalignment, or loosening.

III. Diverse Application Scenarios for Gearless Slewing Bearings

3.1 New Energy Photovoltaic (PV) Industry

LTZC gearless slewing bearings are suitable for a wide range of PV applications, including single-axis horizontal tracking systems, dual-axis full-angle tracking systems, distributed small-scale PV tracking mounts, large-scale ground-mounted PV power plants, and smart residential PV tracking equipment.

3.2 Solar Thermal Power Generation Equipment

With features such as zero backlash, precise rotation, and drift-free long-term operation, LTZC gearless slewing bearings meet the high-precision rotational adjustment requirements of solar thermal reflector arrays. They are designed for stable, long-term outdoor operation in large-scale solar thermal power plants, effectively enhancing solar concentration efficiency and power generation stability.

3.3 Small-scale Construction Machinery and Intelligent Equipment

Thanks to their streamlined structure, smooth operation, and ease of installation, gearless slewing bearings are well-suited for equipment such as small cranes, truck-mounted cranes, and aerial work platforms.

IV. LTZC Gearless Slewing Bearings – 220MW Desert Ground-Mounted PV Tracking Power Plant in Saudi Arabia

Located in the heart of the Arabian Peninsula's desert region, this 220MW large-scale desert photovoltaic (PV) power plant is a key local renewable energy infrastructure project. The site experiences a typical tropical desert climate characterized by the absence of winter and exposure to extreme heat and intense sunlight; summer surface temperatures can exceed 55°C. The area is plagued by frequent sandstorms with coarse, abrasive particles and diurnal temperature fluctuations exceeding 25°C. With peak wind speeds reaching Beaufort Scale 11, the project imposes industry-leading, rigorous requirements on PV tracking bearings regarding sand/dust resistance, high-temperature tolerance, aging resistance, load-bearing capacity, and resistance to jamming.

LTZC Solution: To address the extreme conditions of the Saudi desert—including high temperatures, intense sand and wind, and wide temperature swings—LTZC customized gearless slewing bearings specifically for this overseas project. The design features an upgraded, three-layer thickened wear-resistant dust seal system that comprehensively blocks fine desert sand and hot air currents from entering the bearing. High-temperature special alloy materials and a long-lasting, high-temperature lubricant formula ensure stable, long-term performance in temperatures exceeding 55°C. Finite Element Analysis (FEA) was utilized to reinforce the bearing's overall rigidity, enhancing its resistance to overturning forces from strong winds and deformation, thereby perfectly suiting the harsh local environment.

Project Outcome: Following the full-scale replacement of bearings with LTZC gearless slewing bearings, critical issues such as jamming caused by sand and dust, high-temperature failure, and precision drift were resolved. The equipment's overall annual failure rate dropped by 98%, making it fully compatible with the desert's unmanned operation and maintenance (O&M) model and significantly reducing the high costs associated with manual O&M and equipment replacement. The bearings deliver stable, precise solar tracking performance, resulting in a 13% increase in the power plant's overall generation efficiency and a significant boost in total power output.

LTZC Bearings

With a steadfast commitment to "quality as the core and the customer at the center," LTZC Bearings specializes in providing high-stability, high-precision, long-lifespan, and cost-effective gearless slewing bearing solutions to the global new energy photovoltaic (PV) industry.

Currently, LTZC’s gearless slewing bearings are being supplied in volume to PV enterprises across dozens of countries. Thanks to stable product performance, robust manufacturing capabilities, and comprehensive export services, we have established ourselves as a reliable partner in the global PV tracking system bearing sector.

If you are sourcing gearless slewing bearings for PV tracking systems, require customized non-standard bearings, or are seeking a stable, long-term direct supplier, please feel free to contact the LTZC Bearings team. We offer complimentary services including model selection, application suitability analysis, product quotations, and sample testing, and we look forward to building mutually beneficial partnerships with clients across the global PV industry.