Ningbo Kent Bearing Co., Ltd

“Deep groove ball bearings are the most widely used and highest-consumption core components in drones. Their performance directly determines flight stability, endurance and service life.”   Drones have core requirements for bearings: high speed, lightweight design, low friction and resistance to harsh environments. With their simple structure, strong adaptability and controllable cost, deep groove ball bearings have become the preferred choice for many key subsystems.   Deep groove ball bearings consist of an inner ring, an outer ring, steel balls and a cage. Their deep groove raceways can support both radial and slight axial loads simultaneously without the need for additional thrust bearings, meeting the lightweight requirements of drones. They are mainly used in brushless motors and rotor systems, and are also suitable for components such as small gimbals and steering gears.   As the "heart" of drones, brushless motors can reach tens of thousands of revolutions per minute. Most civilian drones use miniature deep groove ball bearings such as 5×11×4 mm and 8×22×7 mm, which are mounted in pairs at both ends of the motor shaft. Bearings of ABEC-5 precision or higher with 2RS/ZZ sealing are selected. For example, the 608 bearing (inner diameter 8 mm, P6 precision) has a limiting speed of 18,000 rpm and a dynamic load rating of 4.8 kN, making it a standard choice for motors in small civilian drones.   Consumer drone gimbals use even smaller miniature bearings, requiring low friction and low noise (≤20dB). Servos and control linkages adopt chrome steel (GCr15) bearings; after heat treatment, their hardness reaches HRC60–64, improving fatigue resistance.   Offshore operation drones adopt 440C stainless steel bearings for salt spray resistance, while industrial drones used in high-temperature environments are equipped with high-temperature resistant grease rated for -30℃ to +120℃.With outstanding cost performance, deep groove ball bearings have become indispensable basic components in the drone industry.   In summary, the core value of deep groove ball bearings lies in simplifying structure, improving efficiency and controlling costs. They are used across multiple drone systems. With the advancement of drone technology, these bearings are evolving toward higher precision, lighter weight and maintenance-free operation.      

For electric motor production and R&D, whining noise is not only a notorious "quality saboteur" but also a top pain point for most motor manufacturers. Drawing on decades of bearing technology expertise, I have identified that the root cause of the vast majority of motor whining noise issues lies in the selection and matching of bearings. Fix 1: Choose High-Precision Bearings to Suppress Whining at the Source One core cause of motor whining is insufficient bearing precision, which leads to excessively high friction-induced vibration frequencies between the raceways and steel balls during operation.Our high-precision ball bearings adopt nano-level super-finishing grinding technology, controlling radial runout within standard limits and significantly reducing vibration deviations during rotation. Coupled with an optimized raceway curvature design, they minimize high-frequency noise generated by frictional contact—cutting off the possibility of whining at the source. This is also the preferred solution for numerous motor manufacturers to resolve whining problems. Fix 2: Match Low-Friction Quiet Bearings to Suit Diverse Working Conditions Motors used in different application scenarios have varying bearing requirements; blindly using general-purpose bearings can easily trigger whining noise.For instance: Home appliance motors demand silent operation; Power tool motors need to withstand high-frequency start-stop cycles; New energy motors require high-temperature resistance. Our bearings are formulated with premium low-friction lubricants tailored to different motor working conditions. They not only reduce operational noise but also adapt to a wide temperature range of -20°C to 120°C. Furthermore, we offer customized adjustments based on customer-specific motor parameters such as power, rotational speed, and operating conditions, ensuring perfect compatibility between bearings and motors and eliminating whining caused by mismatched working conditions. Fix 3: Strictly Control Bearing Installation & Quality Assurance to Avoid Secondary Whining Even with the right bearings selected, improper installation or quality defects in the bearings themselves can still lead to whining noise.As a direct bearing manufacturer, every batch of our bearings undergoes 12 rigorous inspection procedures including dynamic noise testing and service life testing, ensuring zero quality defects before factory shipment. We also provide customers with professional installation guidelines to avoid issues such as coaxiality deviations and improper preload during assembly. This full-process support—from production to installation—helps manufacturers eliminate the risk of secondary whining noise. In short, there’s no need to worry about solving motor whining noise—the core lies in selecting the right bearings, achieving precise matching, and enforcing strict quality control. Ningbo Kent Bearing has provided over 200 million sets of silent bearing solutions to more than 500+ motor manufacturers worldwide. If your motors are plagued by whining noise issues, or if you want to avoid such problems proactively, feel free to contact the Kenda Technical Service Team at +86-19957028916. We will provide you with a free customized technical bearing selection plan, helping you completely eliminate whining noise troubles and enhance your product competitiveness!

  For motor manufacturers, the excessive friction in motor bearings is a pervasive pain point that impacts every stage of production and the market. Ordinary bearings with high friction resistance demand more electrical energy to overcome resistance during startup, leading to excessive energy consumption. This is particularly detrimental in sectors with stringent energy efficiency requirements, such as new energy vehicles and home appliances, where it can quickly erode competitiveness. Moreover, high friction accelerates wear between bearing raceways and rolling elements, increasing operational noise and shortening the lifespan of both the bearings and the entire motor, which directly drives up repair rates and after-sales costs. Most critically, the heat generated by friction can compromise the stability of internal motor components. In high-load, continuous operation scenarios like those found in garden tools and industrial motors, this can lead to overheating failures and a surge in customer complaints。   The motor bearings produced by Kent are specifically designed to address these pain points. Their core advantage stems from two key technological breakthroughs: first, the use of optimally designed rolling elements paired with micron-polished raceways to reduce the coefficient of friction, ensuring not only a "smooth and resistance-free" operation but also extending the motor's lifespan. Second, the application of a custom low-friction lubricant, which not only minimizes friction between contact surfaces but also maintains stable performance across a wide temperature range of -40°C to 180°C, adapting to various motor operating conditions. The value of low friction is immediately evident: it reduces motor energy consumption to meet efficiency certification standards, minimizes heat generation, significantly enhances operational stability, and reduces noise levels.   For motor manufacturers, selecting motor bearings is not just a "nice-to-have" but a critical factor in "cost reduction and efficiency improvement." It not only helps optimize product performance and create differentiated selling points but also indirectly saves significant costs by reducing energy consumption and minimizing returns. As a direct manufacturer, Kenda focuses on low-friction technology R&D from material selection to process optimization. We can precisely adjust bearing structures and lubrication solutions based on motor speed, load, operating environment, and other conditions, ensuring the low-friction advantage is perfectly tailored to your products.