Cylindrical roller bearing：NN3021

Basic Parameters

• "NN" represents double-row cylindrical roller bearings. The characteristic of double-row cylindrical roller bearings is that they have two rows of rollers. This structure gives it high radial load-carrying capacity and good rigidity. Compared with single-row cylindrical roller bearings, it can provide more stable support under more complex stress conditions, such as simultaneously bearing large radial forces and a certain amount of axial force, and is suitable for heavy loads and equipment with high precision requirements.

• The size series code reflects the width series and diameter series information of the bearing. The size series "30" is a specific specification combination in double-row cylindrical roller bearings and is used to determine the overall size range of the bearing. It helps users find the appropriate bearing size according to the specific installation space and load requirements of the equipment when selecting. For example, different size series may correspond to different equipment types. The "30" series may be more suitable for some medium to large-sized equipment. Its size design can better adapt to the equipment's spatial layout while ensuring load-carrying capacity.

• According to the regulations of bearing inner diameter codes, multiplying the inner diameter code by 5 is the actual inner diameter size of the bearing. So the "21" in NN3021 indicates that the inner diameter of the bearing is 105mm (21×5 = 105). The inner diameter size is a key parameter for the cooperation between the bearing and the shaft. An accurate inner diameter can ensure a tight fit between the bearing and the shaft, enabling the bearing to effectively transmit loads during operation and reducing wear and heat generation, which is crucial for the service life of the bearing and the stable operation of the equipment.
• • 

    NN3021

  • 

    NN3021

  • 

    NN3021

  • 

    NN3021

   

Structural Features

• The NN3021 bearing adopts a dual-row cylindrical roller structure. This design enables the bearing to withstand a large radial load. The two rows of rollers are evenly distributed and can jointly share the load during operation, greatly enhancing the bearing capacity. It is like having two teams of porters with evenly distributed strength, simultaneously bearing the pressure of heavy objects to ensure that the equipment can still operate smoothly under heavy loads.

• Both the inner and outer rings are precisely processed, and their raceways have an extremely high fit with the rollers. The inner ring can provide precise installation positioning for the shaft and ensure the stability of the shaft during rotation. The outer ring can cooperate well with the bearing seat and evenly transmit the load to the supporting structure of the equipment. This tight fit is like a mortise and tenon structure. Each component fits precisely, so that the bearing will not loosen or shift during operation.

• The cage in the bearing plays a key role in the orderly movement of the rollers. The cage of the NN3021 is reasonably designed. It can evenly separate the two rows of rollers and avoid mutual collision and friction between the rollers. This is like arranging an independent working space for each busy "little worker" (roller), allowing them to work efficiently and orderly, thereby reducing energy loss and wear and prolonging the service life of the bearing.

Performance Advantages

 

• Due to its double-row rollers and high-quality structural design, the NN3021 bearing exhibits excellent radial load-carrying capacity. In the field of heavy machinery, such as coal mining machines and other equipment, it can easily handle huge radial forces. For example, in the process of coal cutting by a coal mining machine, huge radial loads are generated. The NN3021 bearing is like a strong guard, stably supporting the rotating parts to ensure the normal operation of the coal mining machine and effectively improving the working efficiency and reliability of the equipment.

• The precision processing technology endows the NN3021 bearing with high-precision operation performance. In equipment with high precision requirements, such as the rotating table of precision machine tools, it can ensure the rotational precision of the equipment. Its low friction coefficient and stable rotation characteristics are like installing a high-precision "gyroscope" on the equipment, enabling the equipment to achieve accurate positioning and movement during operation, thereby improving the quality and precision of processed products.

• The NN3021 bearing also has good adaptability in harsh working environments. Whether in a humid mine environment or in a dusty industrial plant, it can maintain stable performance. This is due to its good sealing performance and high-quality material selection. Even in the presence of unfavorable factors such as impurities and moisture, the bearing can still operate normally, reducing equipment failures caused by environmental factors and lowering maintenance costs.

Product Application

1. Heavy machinery field
   As for coal mining machines mentioned earlier, NN3021 bearing is a key supporting component. In parts such as the drum and cutting part of the coal mining machine, the bearing needs to withstand huge radial force and a certain amount of axial force. With its high load-bearing capacity and stability, NN3021 can ensure the coal mining machine to work stably for a long time in the harsh underground environment and improve the efficiency of coal mining.
2. Industrial transmission equipment
   In some large industrial transmission equipment such as reducers and speed increasers, NN3021 bearing also plays an important role. It can be used as the supporting bearing of high-speed shaft or low-speed shaft. In the process of transmitting power, it can stably bear radial load and ensure the accuracy and high efficiency of transmission. For example, in the reducer of rolling mill in steel plant, NN3021 bearing can ensure the precise meshing of gears and make the rolling process go smoothly.
3. Precision processing equipment
   In high-precision machine tool equipment, NN3021 bearing is used in key parts such as spindle and worktable. For machine tools that need high-precision milling, grinding and other processing, it can provide the required rotational accuracy and stability. For example, in the precision grinding machine for processing aerospace parts, NN3021 bearing can ensure the high-precision rotation of grinding tools, so as to process products that meet strict precision requirements.
4. • 

     coalcutter

   • 

     rolling mill

   • 

     precision grinder

    

Product List