What are the effects of the machining accuracy of the inner and outer ring raceways of the double row ball slewing ring on the performance of the slewing ring?

What is double row ball slewing bearing

Double-row ball slewing bearing is a 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 rings

A double-row ball slewing ring is a mechanical component used to withstand large axial forces, radial forces and overturning moments, with the following characteristics:

Strong bearing capacity: The double row ball slewing ring has two rows of steel balls, which can withstand axial force, radial force and overturning moment at the same time. Compared with the single-row ball slewing ring, its bearing capacity is greatly improved, which can meet the force requirements of large machinery and equipment under complex working conditions, such as large cranes, shield machines and other equipment, which can withstand the huge load generated by lifting heavy objects and various forces during equipment operation.

High Rotation Accuracy: Through precise machining technology and assembly technology, double row ball slewing rings can ensure high rotation accuracy. The matching accuracy of the raceway and the steel ball is high, which can make the equipment stable during rotation and reduce vibration and swing, which is very important for some equipment that requires high precision, such as radar antennas and astronomical telescopes, to ensure that it accurately points to the target and improves the working performance.

Good rigidity: The structural design of the double row ball makes it have good rigidity. When bearing load, it can effectively resist deformation and maintain the stability of the structure. This helps to improve the overall strength and reliability of the equipment, and prolong the service life of the equipment, especially in some heavy-duty and high-impact working environments, such as mining machinery, port machinery, etc., which can better adapt to harsh working conditions.

Stable operation: the steel ball rolls in the raceway, the friction resistance is small, and the distribution of the double row ball makes the load evenly distributed, so as to ensure the stability of the slewing ring in the running process. The equipment runs smoothly when rotating, reducing noise and vibration, improving the quality of the operator's working environment, while also reducing wear and impact on other parts of the equipment.

Easy installation: Double row ball slewing rings are usually designed with standardized mounting interfaces and dimensions for easy connection and installation with other parts of the equipment. Its structure is relatively compact, occupies a small space, and can achieve a large bearing capacity and rotation function in a limited space, which provides convenience for the design and manufacture of equipment.

Low maintenance cost: Due to its simple structure and reliable operation, the maintenance of double row ball slewing rings is relatively easy. It only needs to regularly check the lubrication, sealing performance and wear of components, lubricate and replace worn parts in time, which reduces the maintenance cost and downtime of the equipment and improves the efficiency of the equipment.

What are the effects of the machining accuracy of the inner and outer ring raceways of the double row ball slewing ring on the performance of the slewing ring?

The machining accuracy of the raceway of the inner and outer rings of the double row ball slewing ring has a crucial impact on the performance of the slewing ring, as follows:

Affects the carrying capacity

Raceway dimensional accuracy: If there is a deviation in the dimensional accuracy such as diameter and width of the raceway, the contact area and contact stress distribution between the ball and the raceway will be uneven. For example, the diameter of the raceway is too large or too small, which will change the position of the contact point between the ball and the raceway, resulting in local stress concentration, reducing the bearing capacity of the slewing ring, and in serious cases, it may make the ball or raceway premature fatigue wear, plastic deformation and other failure forms, affecting the service life of the slewing ring.

Raceway shape accuracy: Poor shape accuracy such as cylindricity and roundness will cause the ball to be unevenly stressed when rolling in the raceway. If there is elliptism in the raceway, the contact force between the ball and the raceway will change periodically during the rotation process, which is easy to cause vibration and noise, and will also accelerate the wear of the ball and raceway and reduce the bearing capacity.

Affects the rotation accuracy

Position accuracy of raceway: The position accuracy of the raceway such as coaxiality and parallelism of the inner and outer ring raceways directly affects the rotation accuracy of the slewing bearing. If the coaxiality error is large, the center of rotation will be offset, resulting in shaking or swinging of the equipment during operation, which will affect the machining accuracy or operation stability of the equipment. For example, in a rotary table of a machine tool, insufficient rotation accuracy can lead to a decrease in the dimensional accuracy and surface quality of the machined parts.

Surface roughness: The surface roughness of the raceway affects the friction and lubrication between the ball and the raceway. If the surface is too rough and the friction resistance is large, it will increase the rotating torque, reduce the transmission efficiency, and may also cause heating and aggravation. If the surface is too smooth, it will affect the formation of the lubricating oil film, which is also not conducive to the maintenance of rotation accuracy.

Affect the smooth operation

Dimensional and shape accuracy: The deviation of the size and shape accuracy of the raceway will cause the ball to jump or slide during the rolling process, destroying its smooth rolling state. For example, the local size mutation or irregular shape of the raceway will cause the ball to impact when passing through the area, resulting in vibration and noise during the operation of the slewing ring, affecting the working environment and stability of the equipment.

Surface waviness: The waviness of the raceway surface will cause periodic changes in the contact force between the ball and the raceway, causing vibration and noise. Even a small waviness may be amplified in high-speed rotation or high-precision applications, which seriously affects the smooth operation.

In order to ensure the high performance of the double row ball slewing ring, it is necessary to strictly control the machining accuracy of the inner and outer ring raceways, and adopt advanced processing technology and precision testing equipment to meet the high-precision requirements of the slewing ring in different application fields.

Supplier of double row ball slewing rings

LZTC Double Row Ball Slewing Rings provides a series of services such as R&D, design, production and sales of double row ball slewing ring products. If you are looking for a double row ball slewing ring supplier, please contact us for the latest quote.