What is double row ball slewing ring?

What is double row ball slewing ring

Double-row ball slewing bearing is slewing ring bearing that consists of two rows of balls and is used to handle a combination of axial, radial, and moment loads. This design improves the load distribution and performance of the bearing, making it suitable for heavy-duty applications. It is often used in machinery that needs to rotate effectively under large loads.

Features of double row ball slewing ring

Double row ball slewing bearings have the following characteristics:

High load - carrying capacity: The double - row ball structure enables them to bear large axial, radial, and moment loads simultaneously. The two rows of balls distribute the load, enhancing the bearing's overall load - carrying capacity, allowing it to handle heavy loads in applications such as cranes and excavators.

Compact structure: Despite their high load - bearing capacity, they maintain a relatively compact size and light weight. This makes them suitable for use in equipment where space is limited, enabling efficient installation and operation without occupying excessive space.

Good rotational accuracy: They ensure smooth and precise rotation. The balls roll smoothly within the raceways, minimizing rotational errors and vibrations, which is crucial for applications requiring high - precision motion, such as in robotics and aerospace equipment.

Self - aligning ability: To some extent, they can accommodate misalignment between the rotating and stationary components. This self - aligning feature provides greater tolerance for mechanical errors or distortions in the system, reducing the impact of misalignment on the bearing's performance and service life.

Wide range of applications: Due to their excellent comprehensive performance, they are widely used in various fields, including construction machinery, mining equipment, wind turbines, and marine engineering. They can meet the diverse requirements of different types of equipment for load - bearing and rotation.

Good sealing and lubrication: They usually have reliable sealing and lubrication systems. The sealing structure effectively prevents the ingress of dust, water, and other contaminants, while the lubrication system ensures the smooth operation of the balls and raceways, reducing wear and friction and prolonging the bearing's service life.

The principle of double - row ball slewing bearings is mainly based on the rolling friction principle and a special structural design, as detailed below:

Rolling Friction Principle

Double - row ball slewing bearings are mainly composed of an inner ring, an outer ring, two rows of steel balls, and a cage. When an external force acts on the inner or outer ring, causing it to rotate relative to the other, the steel balls roll between the raceways of the inner and outer rings. In this process, rolling friction replaces sliding friction. Since the coefficient of rolling friction is much smaller than that of sliding friction, it enables a smooth relative rotation with low frictional resistance. This makes the slewing motion more fluent and effectively reduces energy consumption.

Structural Design Principle

The double - row ball structural design endows the bearing with the ability to withstand large axial forces, radial forces, and overturning moments. The two rows of steel balls are arranged with a certain angular offset from each other. This layout evenly distributes various forces acting on the slewing bearing to each steel ball, thus enhancing the bearing's load - carrying capacity and stability. Meanwhile, the cage serves to evenly space the steel balls, preventing them from colliding and rubbing against each other. This ensures that the steel balls can roll stably within the raceways, further improving the performance and service life of the slewing bearing.

The principle of double row ball slewing bearings

The principle of double - row ball slewing bearings is mainly based on the rolling friction principle and a special structural design, as detailed below:

Rolling Friction Principle
Double - row ball slewing bearings are mainly composed of an inner ring, an outer ring, two rows of steel balls, and a cage. When an external force acts on the inner or outer ring, causing it to rotate relative to the other, the steel balls roll between the raceways of the inner and outer rings. In this process, rolling friction replaces sliding friction. Since the coefficient of rolling friction is much smaller than that of sliding friction, it enables a smooth relative rotation with low frictional resistance. This makes the slewing motion more fluent and effectively reduces energy consumption.

Structural Design Principle
The double - row ball structural design endows the bearing with the ability to withstand large axial forces, radial forces, and overturning moments. The two rows of steel balls are arranged with a certain angular offset from each other. This layout evenly distributes various forces acting on the slewing bearing to each steel ball, thus enhancing the bearing's load - carrying capacity and stability. Meanwhile, the cage serves to evenly space the steel balls, preventing them from colliding and rubbing against each other. This ensures that the steel balls can roll stably within the raceways, further improving the performance and service life of the slewing bearing.

What are the application areas of double row ball slewing rings?

Double - row ball slewing bearings are widely used in various fields due to their characteristics of high load - carrying capacity and good rotation accuracy. The following are some of their main application areas:

Construction Machinery: In tower cranes, they support the rotation of the upper structure, enabling the crane to lift and move heavy objects in different directions. Mobile cranes also use double - row ball slewing bearings to achieve flexible rotation of the boom, improving the operational efficiency and range of the crane.

Mining Equipment: For example, in rotary drilling rigs, double - row ball slewing bearings provide reliable rotation support for the drilling mechanism, allowing it to work efficiently under harsh mining conditions. In addition, some mining conveyors use this type of bearing to ensure the smooth rotation of the conveyor rollers.

Wind Turbines: They are used in the connection between the nacelle and the tower of wind turbines. The double - row ball slewing bearings can withstand the large axial and radial forces generated during the operation of the wind turbine, ensuring the stable rotation of the nacelle and improving the efficiency of power generation.

Solar Trackers: In solar power generation systems, solar trackers use double - row ball slewing bearings to track the movement of the sun. This allows the solar panels to always face the sun at the optimal angle, maximizing the absorption of solar energy and improving the power generation efficiency.

Industrial Robots: In industrial robots, especially those used for material handling and assembly, double - row ball slewing bearings are used in the joints of the robot arms. They provide precise rotation and high load - carrying capacity, enabling the robot arms to move accurately and handle heavy objects.

Medical Equipment: Some medical imaging equipment, such as CT scanners and medical X - ray machines, uses double - row ball slewing bearings to achieve the rotation of the scanning part. This ensures the accuracy and stability of the scanning process, helping medical staff obtain high - quality images.

Aerospace and Defense: In some aerospace and defense applications, such as radar antenna rotation systems and missile launch platforms, double - row ball slewing bearings are used to provide reliable rotation support. They can withstand high - speed rotation and large - scale loads, meeting the high - performance requirements of aerospace and defense equipment.

Supplier of double row ball slewing rings

LTZC Bearings is a professional manufacturer of slewing rings, slewing rings, slewing drives, and bearing components, providing quality and advanced solutions to customers worldwide. If you are looking for double row ball slewing rings for your project, please do not hesitate to contact us.