Ningbo Kent Bearing Co., Ltd

‌  In the field of electric motors, the placement of positioning bearings in vertical motors is critically important and requires comprehensive consideration of multiple factors.    ‌From the perspective of motor structure and force analysis:‌ In horizontal motors, bearings primarily withstand radial loads, whereas in vertical motors, rotor gravity converts to axial loads. Typically, one end is fixed (positioning) to bear axial forces, thus requiring bearings capable of handling axial loads. ‌Selection of positioning bearing location is influenced by external loads on the shaft extension end:‌ Example: In vertical pump motors, the shaft extension connects to impellers and faces radial impact from water flow. If the positioning bearing is placed at the lower (shaft extension) end, it must simultaneously endure rotor gravity and radial hydraulic forces, accelerating wear. ‌Case Study‌: Kenda Bearing served a pump manufacturer where improper positioning bearing placement reduced bearing life to 60% of the design value. After relocating the positioning bearing to the upper end (with the lower end floating), service life extended to 1.5 times the original. ‌Maintenance accessibility is equally critical:‌ Positioning bearings endure combined loads (axial + radial), demanding frequent maintenance. For vertical motors in harsh environments (e.g., mining equipment), maintenance complexity increases if the positioning bearing is on the non-shaft-extension end, as it may require disassembling auxiliary components like fans or covers. ‌Conclusion:‌There is no universal answer for positioning bearing placement in vertical motors. Optimal selection must integrate motor structure, shaft-end load conditions, and maintenance feasibility to ensure stable and efficient operation.

  Within the critical components of electric motor operation, deep groove ball bearings stand as the most widely adopted solution due to their distinctive advantages.   The structural design of deep groove ball bearings embodies sophisticated engineering. Comprising an inner ring, outer ring, rolling elements, and cage, their deep-groove-profile raceways enable simultaneous handling of radial loads and bidirectional axial loads – earning them the title of 'universal joints' in electric motors. The curvature radii of raceways and rolling elements undergo meticulous calculation, optimizing contact area while minimizing friction coefficients. During high-speed motor operation, the cage uniformly spaces rolling elements to prevent frictional collisions. Coupled with high-performance grease, this design confines temperature rise within ideal parameters – a critical factor for continuously operated motors.   In terms of performance compatibility, deep groove ball bearings are optimally aligned with electric motor requirements. Most standard motors operate at 1500-3000 r/min—well within the limiting speed range of these bearings, which can even accommodate certain high-speed motor applications. Their radial clearance is adjustable according to operational demands, spanning from the minimal clearance of C2 grade to the increased clearance of C4 grade, thereby accommodating shaft expansion across diverse temperature environments.  Installation simplicity further drives their ubiquity. Deep groove ball bearings tolerate minor coaxiality deviations during motor assembly, eliminating stringent alignment requirements. Versatile models serve applications from light-load scenarios in small appliance motors to medium-load industrial drives. For instance:     Household A/C compressor motors typically employ 6205 series bearings.     Auxiliary spindle motors in machine tools frequently utilize 6310 bearings with ZZ shields.   Advancements in materials and manufacturing further enhance their capabilities. Rings and rolling elements forged from high-carbon chromium bearing steel (GCr15) achieve HRC 60-65 hardness after quenching and tempering, delivering exceptional wear resistance. Seal configurations—ranging from non-contact rubber shields (2RS) to contact seals (2RZ)—offer flexible selection based on motor IP requirements, effectively blocking particulate and oil contaminants   From micro stepping motors to large induction motors, deep groove ball bearings serve as indispensable fundamental components in the electromechanical industry. Their well-rounded performance characteristics, universal adaptability, and cost efficiency collectively underpin the stable operation of countless devices     Kent Bearings delivers silent operation solutions to 500+ global motor manufacturers, with over 200 million units deployed. Contact our Technical Service Team at +86-19957451956 for complimentary motor-bearing compatibility validation services. Unlock quantifiable ROI through precision quietness upgrades!

  Selecting the appropriate bearing clearance requires comprehensive consideration of factors such as bearing type, operating conditions, fit methods, and other multifaceted aspects to ensure the bearing achieves optimal performance during operation (long life, low heat generation, minimal vibration, stable accuracy).     Core Influencing Factors     Operating Conditions:   1. Load Conditions‌ Heavy-load scenarios: Select slightly larger clearance to avoid bearing contact stress concentration. Light-load high-precision applications: Opt for smaller clearance. ‌   2. Rotational Speed‌ High-speed operation: Reserve greater clearance to compensate for thermal expansion (pronounced temperature rise during rotation). Low-speed heavy-load conditions: Choose smaller clearance to enhance rigidity.  ‌   3. Temperature Environment‌ High/low temperature extremes: Select larger clearance to counteract clearance reduction caused by differential thermal expansion between inner and outer rings. Fitting Methods: 1. Interference Fit for Inner Ring‌ When the inner ring adopts an interference fit with the shaft, it induces ring expansion, reducing radial clearance. Compensation requires selecting a ‌larger initial clearance group‌ (e.g., C3/C4). ‌2. Interference Fit for Outer Ring‌ An interference fit between the outer ring and housing causes ring contraction, similarly decreasing clearance. This necessitates ‌elevating the clearance grade‌. ‌3. Clearance Fit‌ For clearance fits between rings and mating surfaces, standard clearance groups (e.g., CN/C0) may be applied without compensation adjustments. Bearing Types ‌    1. Self-Aligning Bearings & Cylindrical Roller Bearings‌     Require larger clearance groups to accommodate self-alignment or compensate for deformation. ‌    2. Angular Contact Ball Bearings & Tapered Roller Bearings‌     Typically require controlled clearance via ‌preload‌ to enhance rigidity.  ‌   3. Deep Groove Ball Bearings‌     Select clearance groups (CN/C2/C3) based on temperature and vibration requirements.