Deep groove ball bearings are the most widely used rolling bearings globally. Constructed with integrated arc raceways and steel balls, they bear radial loads and slight bidirectional axial loads simultaneously. Featuring simple structure, high limiting speed, low rotational noise and strong adaptability for maintenance-free sealed versions, the non-separable inner and outer rings enable easy installation. Classified into open type, Z metal shield dust-proof type and 2RS double rubber seal waterproof & dust-proof type, they cover mainstream dimensions of 6000, 6200, 6300 and 6400 series, serving as standard bearings for industrial motors, centrifugal fans, clean water pumps, air compressors, household appliances, conveyor rollers and auxiliary supports for gearboxes.

Compared with cylindrical roller bearings, deep groove ball bearings deliver higher maximum rotating speed, smoother silent operation and lighter weight for small and medium high-speed rotating equipment. Versus angular contact ball bearings, they require no paired preload assembly, offering superior versatility and lower procurement & replacement costs. The main disadvantage is limited heavy-load capacity and poor resistance to impact loads, making them suitable only for rotary mechanisms with medium-small load, continuous high speed and stable working conditions.

Three-phase asynchronous motors, cooling tower fans and horizontal centrifugal pumps run non-stop for long periods. Inferior deep groove ball bearings feature poor roundness of steel balls and rough raceway surfaces, causing severe vibration and noise at high speed. Aging-resistant performance of sealing rubber rings is insufficient, allowing water vapor and dust to penetrate inside the bearing and degrade grease, resulting in bearing seizure, motor stator rubbing, water intrusion into pump bearings and abnormal fan vibration, which further leads to motor burnout and full-unit shutdown maintenance.

NMT deep groove ball bearings cover full-size series of 6000, 6200, 6300 and 6400, complete with open type, single-side metal shield Z, double-side metal shield ZZ and double rubber seal 2RS. Forged from high-cleanliness bearing steel, inner and outer raceways are superfinely ground, and high-precision graded steel balls are selected for assembly. Standard international dimensions support direct replacement of domestic and imported deep groove ball bearings for OEM assembly and after-sales maintenance.

General industrial and civil equipment impose rising requirements on bearing silence, long-term sealing performance and continuous operation stability. Conventional bearings suffer rough raceway machining, easy cracking of sealing components under aging and insufficient grading accuracy of steel balls, leading to obvious heat generation and rapid failure from water/dust intrusion during long-time high-speed operation. They fail to meet working demands of water pumps in humid outdoor environments, 24-hour continuous operation of fans and frequent start-stop of variable-frequency motors. The market demands general-purpose deep groove ball bearings with high-precision silent performance, durable sealing and controllable temperature rise.

NMT deep groove ball bearings adopt mirror superfinishing for inner and outer raceways. The accurate arc contour fits steel balls closely to evenly disperse contact stress, cutting friction loss, temperature rise and noise during high-speed rotation. High-precision graded steel ball assembly eliminates vibration caused by mixed use of balls with different sizes. The 2RS rubber seal is made of temperature-resistant nitrile butadiene rubber with built-in spring tightening structure for excellent waterproofing, dustproofing and grease retention, ideal for humid and dusty scenarios of water pumps and outdoor fans. ZZ metal dust covers are suitable for indoor dry fans and motors to block dust and extend grease service life. Open bearings support on-site grease refilling for high-temperature equipment.

Stamped cold-rolled steel cages realize lightweight design for high-speed rotation; large-size models adopt nylon cages for better noise reduction. All finished bearings pass high-speed temperature rise test, noise classification inspection and water immersion sealing test to eliminate defective products with raceway defects, steel ball dimensional deviation and seal leakage, ensuring stable long-term operation.

Core Product Advantages

Integrated deep groove raceway accommodates radial load and bidirectional light axial load for most general rotary equipment.

Precision raceways and graded steel balls achieve low noise and low heat at high speed, resisting overheating during frequent start-stop of variable-frequency motors.

Multiple sealing options: 2RS for waterproof & dustproof, ZZ for dustproof, open type for relubrication, adapting to dry and humid working conditions.

Standard universal dimensions for direct interchange, no modification needed for installation during equipment repair and replacement.

Compact stamped steel cages reduce rotational resistance for excellent high-speed response.

Aging and temperature-resistant seals prevent water intrusion failure for outdoor water pumps and cooling tower fans.

Factory noise classification screening reduces abnormal operation noise and improves overall equipment quality.

Stable mass production and sufficient stock support bulk procurement for complete machine assembly.

Typical Application Scenarios

Y-series three-phase motors, variable-frequency motors, small geared motors; cooling tower fans, centrifugal fans, axial fans; clean water centrifugal pumps, circulating water pumps, small oil pumps; auxiliary shafts of screw air compressors, blowers; conveyor rollers, small gearboxes; fan coil units, air compressors, washing machines, outdoor air conditioner motors and other civil motors; woodworking machinery, small machine tool transmission shafts.

Quality Assurance

NMT implements standardized precision machining for deep groove ball bearings: spheroidizing annealing of bearing steel forgings refines metallographic structure to enhance toughness and fatigue resistance; forming grinding and superfinishing for inner and outer raceways reduce surface roughness; steel balls are assembled by precision grading to ensure uniform clearance distribution; sealing parts undergo thermal aging pretreatment to avoid hardening failure under high temperature. Finished bearings are divided into C0 normal clearance and C3 enlarged clearance high-speed models according to rotating speed to release thermal expansion stress for high-speed motors. Delivered bearings feature smooth rotation, uniform noise and reliable sealing for round-the-clock regular operation of industrial and civil equipment.

Product Range

6000, 6200, 6300, 6400 series deep groove ball bearings; OPEN open type, single-side Z metal shield, double-side ZZ metal shield, double-side 2RS rubber seal; stamped steel cages, nylon cages; C0 standard clearance, C3 enlarged clearance high-speed dedicated models.

Brand Strength

NMT Japan targets three typical defects of ordinary deep groove ball bearings: loud noise at high speed, water/dust ingress through seals and excessive temperature rise after long-time operation. Optimizations including superfinishing of raceways, selection of high-precision steel balls and reinforced sealing structure greatly upgrade bearing silence, protection performance and long-term operation stability. It provides cost-effective general bearing supporting for motor manufacturers, fan & water pump producers and electromechanical maintenance merchants to cut abnormal noise and bearing damage failures of equipment.