How to Select a Double Row Ball Slewing Bearing
In the operation of numerous mechanical devices, the double row ball slewing bearing plays a crucial role, directly influencing the performance, stability, and service life of the equipment. To choose a suitable double row ball slewing bearing, it is necessary to comprehensively consider multiple factors.
What is Double Row Ball Slewing Bearing?
The double row ball slewing bearing is a type of slewing bearing, mainly composed of components such as an inner ring, an outer ring, two rows of steel balls, and spacers. Its unique structure features two rows of steel balls. Compared with single row ball slewing bearings, this design significantly enhances the load – carrying capacity, enabling it to simultaneously withstand large axial forces, radial forces, and overturning moments. It is widely used in various large – scale mechanical equipment, such as port cranes, large – scale excavators, and wind power generation equipment. It can ensure the smooth and flexible rotation of key components of the equipment, and is a key mechanical component for ensuring the normal operation and efficient operation of these devices. It plays an important role in enhancing the performance and reliability of the equipment.
Key Factors in Selecting a Slewing Bearing
The double row ball slewing bearing needs to withstand axial forces, radial forces, and overturning moments. It is necessary to accurately calculate various loads generated during the operation of the equipment and determine the load – carrying capacity requirements of the slewing bearing according to the actual working conditions. For example, when a large – scale crane is lifting heavy objects, the slewing bearing not only has to bear the gravity of the heavy objects (radial force), but also has to cope with the overturning moment generated by the rotation of the boom. If the load – carrying capacity is insufficient, the slewing bearing is prone to premature wear, deformation, or even failure. Excessive load – carrying capacity will increase costs and cause waste of resources. When calculating, relevant formulas in mechanical design manuals can be referred to, and accurate calculations can be carried out by combining parameters such as the equipment’s working class, maximum lifting capacity, and slewing radius.
Accuracy is equally important. Different devices have significantly different accuracy requirements for slewing bearings. Equipment such as precision machine tools and robots require slewing bearings to have extremely high rotational accuracy to ensure the accuracy of processing or operation. For some ordinary construction machinery with relatively low accuracy requirements, such as small loaders, the accuracy requirements are not so strict. The accuracy of slewing bearings mainly includes indicators such as radial run – out, axial run – out, and end – face run – out. When selecting, it is necessary to choose products that meet the corresponding accuracy levels according to the accuracy requirements of the equipment. Generally, the higher the accuracy level, the higher the price. Therefore, it is necessary to reasonably select the accuracy level on the premise of meeting the equipment’s usage requirements.
Speed limits also need to be carefully considered. Each double row ball slewing bearing has its allowable maximum speed. If the actual working speed of the equipment exceeds the limit speed of the slewing bearing, it will lead to increased friction and severe heat generation, thus shortening the service life of the slewing bearing and even causing malfunctions. When selecting, it is necessary to clarify the normal working speed range of the equipment and ensure that the maximum speed of the selected slewing bearing is greater than the working speed of the equipment. At the same time, the impact of speed changes on the slewing bearing, such as the impact during start – up and shutdown, also needs to be considered. For working conditions with high speeds, slewing bearings with good lubrication performance and lightweight rolling elements can be selected.
The size specification is the basis for selection. It is necessary to determine the outer dimensions of the slewing bearing, including the outer diameter, inner diameter, and width, according to the structure and installation space of the equipment. At the same time, details such as the position, size, and number of installation holes also need to be considered to ensure that the slewing bearing can be perfectly adapted to the equipment. If the size is too large or too small, it cannot be installed and used normally. In the design stage, sufficient installation space for the slewing bearing should be fully considered and reserved. When selecting, the size parameters of the product should be carefully checked to avoid installation problems.
The sealing and lubrication conditions are directly related to the service life of the slewing bearing. Good sealing can effectively prevent the intrusion of dust, impurities, and moisture, avoiding the wear and corrosion of the rolling elements and raceways. Common sealing methods include rubber seals and labyrinth seals. The appropriate sealing form should be selected according to the working environment of the equipment. In dusty and humid environments, rubber seals with good sealing performance should be selected and regularly inspected and replaced. In clean and dry environments, labyrinth seals may be sufficient to meet the requirements. In terms of lubrication, it is necessary to ensure that the slewing bearing is well – lubricated to reduce friction and wear. Different types of slewing bearings have different requirements for lubricants. Appropriate lubricants should be selected according to the product instructions and added or replaced regularly.
The material quality determines the performance and reliability of the slewing bearing. Common materials for slewing bearings include high – quality carbon steel and alloy steel. High – quality materials have characteristics such as high strength, high hardness, good wear resistance, and corrosion resistance. When selecting, attention should be paid to the quality of the materials and the heat treatment process. Materials subjected to appropriate heat treatment can further improve their comprehensive performance. For slewing bearings used in harsh working conditions, such as high – temperature, heavy – load, and strong – corrosion environments, special materials or products with surface treatment, such as carburized and quenched alloy steel, should be selected to improve their performance and service life.
The manufacturing process affects the quality and accuracy of the slewing bearing. Advanced manufacturing processes can ensure the dimensional accuracy, surface quality, and assembly quality of the slewing bearing. When selecting, it is necessary to understand the manufacturing process level of the manufacturer, such as the advancement of processing equipment, the standardization of the production process, and the perfection of the quality control system. The manufacturing process can be evaluated by visiting the manufacturer, checking product samples, and understanding user reviews. Products processed by numerical control machine tools, assembled automatically, and strictly quality – tested are more reliable in quality and more stable in performance.
The Price of Double Row Ball Slewing Bearings
There are many factors affecting the price of slewing bearings. Firstly, raw materials. High – quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is also high. Secondly, slewing bearings with complex manufacturing processes and high – precision requirements require advanced equipment and strict quality control, so the price will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price. Brands and manufacturers’ reputations are also crucial. Well – known brands invest a lot in research and development, production, and after – sales service. Their products are of reliable quality, and the prices are also on the high side. Finally, the market supply – and – demand relationship affects the price. When the demand is strong and the supply is tight, the price rises; otherwise, it falls.
Suppliers of Double Row Ball Slewing Bearings
In terms of quality control, ldb bearing company does an excellent job. Every link from the incoming of raw materials to the outgoing of finished products is strictly controlled. Raw materials are multi – dimensionally tested to ensure their quality compliance. During the production process, every processing step is strictly inspected, and detailed records are kept. Before the finished products leave the factory, comprehensive performance tests are carried out, and only products that fully meet the standards can enter the market.
