Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
Submit
69 Series
Home Deep Groove Ball Bearings 69 Series

6921-2RS Thin-Section Deep Groove Ball Bearing for Industrial Machinery & Automation | 105×145×20 mm

6921-2RS Thin-Section Deep Groove Ball Bearing for Industrial Machinery & Automation | 105×145×20 mm

Developed to support reliable radial and multi-directional axial loads within tight radial profiles, the 6921-2RS is a premium thin-section deep groove ball bearing equipped with dual synthetic rubber seals. Outfitted with heavy-duty contact seals (2RS), it provides a highly resilient barrier against fine dust, moisture, and particulate contaminants while preventing internal grease migration. Because these reinforced rubber lips maintain direct contact with the inner ring recess, the 6921-2RS ensures structural protection and lubrication retention in harsh environments. This makes it an invaluable mechanical component for large-bore, weight-sensitive 105mm shaft applications, including industrial robotic joints, heavy manufacturing automation, and rotating platforms.

6921-2RS Deep Groove Ball Bearing 105x145x20 mm | Thin-Walled Architecture | Double Rubber Sealed

Manufactured to precise international standards, this thin-section bearing allows engineers to maximize space efficiency without sacrificing structural integrity. The signature narrow profile drastically reduces overall assembly weight, enabling cleaner integration into large-diameter hollow shafts and low-profile housings. The contact rubber seals safeguard the micro-honed steel raceways from abrasive contamination, absorbing minor misalignments and cutting down maintenance overhead. As a result, the 6921-2RS delivers exceptionally stable operational endurance, standing out as a long-term powerhouse for demanding industrial drive systems.

6921-2RS Thin-Section Deep Groove Ball Bearing for Industrial Machinery & Automation | 105×145×20 mm

Comprehensive Applications

Engineered for large-bore, narrow-clearance industrial and mechanical systems:

Electrical & Power Transmission
  • Large-diameter electric motors and generators
  • Variable speed gearboxes and speed reducers
  • Wind turbine pitch control systems and monitoring components
  • Power distribution rotary contacts
Industrial Robotics & Automation
  • Multi-axis robotic arm articulation joints and slewing bases
  • Hollow-shaft servo motor assemblies and rotary actuators
  • Automated pick-and-place material handling gantries
  • AGV (Automated Guided Vehicle) wheel hubs and drive units
Specialized Hardware & Marine
  • Packaging machinery rotary turntables and sealing rings
  • Marine winch mechanisms and deck crane pivots
  • Fitness equipment pulleys and high-capacity flywheel mounts
  • Automated commercial gate operator systems
Manufacturing & Heavy Equipment
  • High-precision textile machinery spindles and looms
  • Commercial printing press cylinders and paper feed rollers
  • Industrial fluid pumps and high-volume ventilation fans
  • Material processing conveyors and sorting machinery

Key Performance Features

01. High-Efficiency Thin-Section Geometry

Featuring a large 105mm bore paired with a streamlined 145mm outer diameter, this bearing provides an optimal balance between large shaft capacity and low radial space requirements. The double rubber seals (2RS) secure the internal components from high-grit dust and moisture splashback, ensuring industrial machinery operates continuously without premature breakdown or power loss.

02.Vacuum-Degassed Chrome Steel (GCr15)

Despite its thin-walled cross section, the 6921-2RS is forged from high-purity GCr15 chrome steel. Specialized thermal conditioning ensures the structural raceways and rolling elements achieve uniform hardness and exceptional fatigue resistance, minimizing frictional heat buildup and dampening system vibrations under high load conditions.

03. Advanced Double-Lip Rubber Seals

The primary protective feature of the 2RS series is the chemical-resistant nitrile butadiene rubber (NBR) seal bonded to steel reinforcements. This configuration creates a tight, continuous contact seal that shuts out external moisture and debris while safely sealing in the factory-applied high-performance lubricating grease for life.

Technical Specifications

Bearing Type Single Row Deep Groove Ball Bearing
ISO Dimension Series 6900 Series (Thin Section / Metric)
Basic Designation 6921
Suffix 2RS (Double Rubber Contact Seals)
Bore Diameter (d) 105 mm
Outer Diameter (D) 145 mm
Width (B) 20 mm
Material (Races & Balls) Chrome Steel (GCr15 / SAE 52100)
Precision Class Standard / P5 Grade Available
Seal Material Nitrile Butadiene Rubber (NBR) with Steel Backing
Dynamic Load Rating (Cʳ) 42.5 kN
Static Load Rating (C₀ʳ) 42.0 kN
Limiting Speed (Grease) 2,500 r/min
Limiting Speed (Oil) 5,100 r/min (Open Base Reference)
Weight (approx.) 0.82 kg

Interchange Part Numbers

Directly drops into assemblies utilizing the following equivalent competitor part numbers:

  • SKF/FAG: 61921-2RS1 / 61921-2RSR
  • NSK: 6921DDU
  • KOYO: 6921-2RS
  • NTN: 6921LLU

Design & Configuration

Shipped ready for deployment, the standard Welink 6921-2RS comes pre-lubricated with standard industrial-grade lithium grease optimized for structural damping and moderate temperature spans. For high-corrosion or sanitization-heavy environments, we also manufacture this profile in AISI 440C stainless steel (S6921-2RS). If your application operates under intense thermal environments or high-vibration criteria, contact our technical support division to discuss specialized internal clearances (such as C3 or C4) and high-temperature grease configurations.

"By pairing a massive 105mm bore capacity with an ultra-lean thin-section layout, the 6921-2RS delivers optimal space management and uncompromising reliability to heavy industrial equipment designs."

Related Products

Precision 6921-ZZ Thin Section Bearing 105x145x20mm compatible with SKF 6921-2Z and NSK 6921ZZ for Industrial Robotic Joints and Rotary Tables
6921-ZZ Thin-Section Deep Groove Ball Bearing for Industrial Automation & Heavy Machinery | 105×145×20 mm

Designed specifically for space-constrained, large-shaft assemblies requiring high radial rigidity and minimized weight, the 6921-ZZ is a premium thin-section deep groove ball bearing. Outfitted with dual non-contact metallic shields (ZZ), it delivers exceptional defense against coarse dust and factory debris while ensuring reliable containment of the factory-applied lubrication. Because the metal shields avoid contact friction with the inner ring, the 6921-ZZ maintains minimal running torque and ultra-smooth rotation. This makes it an essential mechanical component for large-bore, weight-sensitive 105mm applications, including industrial robotic joints, heavy-duty rotary tables, and complex automated equipment.

Details
Industrial 6921-2RS Deep Groove Ball Bearing 105x145x20mm featuring Double Rubber Seals for Dust Protection in Industrial Robotics and Heavy Machinery
6921-2RS Thin-Section Deep Groove Ball Bearing for Industrial Machinery & Automation | 105×145×20 mm

Developed to support reliable radial and multi-directional axial loads within tight radial profiles, the 6921-2RS is a premium thin-section deep groove ball bearing equipped with dual synthetic rubber seals. Outfitted with heavy-duty contact seals (2RS), it provides a highly resilient barrier against fine dust, moisture, and particulate contaminants while preventing internal grease migration. Because these reinforced rubber lips maintain direct contact with the inner ring recess, the 6921-2RS ensures structural protection and lubrication retention in harsh environments. This makes it an invaluable mechanical component for large-bore, weight-sensitive 105mm shaft applications, including industrial robotic joints, heavy manufacturing automation, and rotating platforms.

Details
Unshielded 6921 Open Deep Groove Bearing 105x145x20mm compatible with SKF 6921 and NSK 6921 for Industrial Gearboxes and Oil Bath Lubrication Systems
6921 Open Thin-Section Deep Groove Ball Bearing for Gearboxes & Oil-Lubricated Systems | 105×145×20 mm

Engineered for internal mechanical assemblies where external sealing is provided by the housing, the 6921 Open is a high-performance thin-section radial ball bearing. Completely unshielded and unsealed, this open-type configuration allows for unrestricted flow of fluid lubricants directly into the rolling elements. Because there are no physical barriers or rubbing seals, the 6921 Open achieves absolute zero shield-induced friction, ensuring optimal thermal dissipation and maximum rotational efficiency. It is the ideal component for heavy-duty 105mm shaft applications enclosed in oil bath environments, such as industrial transmissions, large centrifugal pumps, and enclosed machine tool spindles.

Details
6920-2RS Deep Groove Ball Bearing featuring Double NBR Rubber Seals for maximum moisture and debris protection in harsh industrial environments
6920-2RS Thin-Section Sealed Ball Bearing for Industrial Machinery & Heavy Automation | 100×140×20 mm

Designed for heavy-duty industrial applications where radial space is limited but environmental protection is paramount, the 6920-2RS is a high-performance thin-section deep groove ball bearing. Equipped with twin nitrile rubber contact seals (2RS), this bearing excels at locking in premium factory grease while completely blocking the ingress of moisture, dust, and abrasive particulate matter. While the contact seals introduce slightly more friction than unsealed or metal-shielded counterparts, they provide unparalleled longevity and reliability in harsh, contamination-prone operating environments, making the 6920-2RS an exceptional solution for 100mm bore requirements in gearboxes, large robotics, and agricultural equipment.

Details
6918 Open Deep Groove Ball Bearing 90x125x18mm Unsealed for Oil Lubricated Industrial Gearboxes and Machine Tools
6918 Unsealed Thin-Section Ball Bearing for Precision Machinery & Heavy-Duty Gearboxes | 90×125×18 mm

Engineered for internal mechanical applications where external contamination is not a factor, the 6918 is a premium open-type deep groove ball bearing. Featuring an unsealed, shield-free architecture, this bearing offers absolute zero seal friction, allowing the internal rolling elements to interact directly with oil-bath or circulating lubrication systems. This unrestricted flow makes the 6918 the ultimate choice for large-bore (90mm) applications requiring superior thermal dissipation and ultra-smooth rotation, such as heavy industrial transmissions, machine tool spindles, and aerospace components.

Details
85x120x18mm 6917-2RS Sealed Ball Bearing compatible with NSK 6917DDU and SKF 6917-2RS1 for Packaging Machinery and Automated Conveyors
6917-2RS Precision Sealed Ball Bearing | 85×120×18 mm for Conveyor Systems & Automated Drives

Engineered to deliver exceptional reliability in environments where radial space is restricted, the 6917-2RS is a premium thin-section deep groove ball bearing. Featuring dual nitrile rubber contact seals (2RS), this bearing is specifically designed to lock in factory lubrication while creating an impenetrable barrier against environmental contaminants like dust, moisture, and manufacturing debris. While rubber seals introduce a nominal increase in friction compared to open bearings, they drastically extend the service life of the component in exposed conditions. This makes the 6917-2RS an invaluable asset for 85mm bore applications, including packaging machinery, medium-duty gearboxes, and automated material handling systems.

Details
Thin Section 6919-ZZ Ball Bearing with Double Metal Shields for 95mm Shaft Applications in Robotics and Industrial Motors
6919-ZZ Thin-Section Deep Groove Ball Bearing | 95×130×18 mm for Space-Constrained Machinery & Large Shafts

Engineered for precision applications where space is at a premium and weight reduction is critical, the 6919-ZZ is a high-performance thin-section deep groove ball bearing. Featuring dual pressed-steel shields (ZZ), it guards internal raceways against dust contamination while retaining factory-filled lubricant. The non-contact design of these metal shields minimizes rotational drag and heat generation, making it an ideal choice for 95mm shaft configurations including industrial automation, large electric motors, and rotary tables.

Details
6915-2RS Thin Section Deep Groove Ball Bearing 75x105x16mm showing NBR Rubber Contact Seals for Robotics and Machine Tool Spindles
6915-2RS Thin Section Deep Groove Ball Bearing for Robotics & Precision Automation| 75×105×16 mm

Engineered for applications where space conservation and weight reduction are critical, the 6915-2RS is a premium thin-section deep groove ball bearing from the 6900 series. Equipped with dual synthetic rubber contact seals (2RS), this bearing offers unparalleled defense against moisture, coolant, and harsh industrial debris while permanently retaining its high-performance factory grease. By utilizing contact sealing technology, the 6915-2RS provides maximum environmental protection, making it an ideal solution for large-diameter shaft applications such as industrial robotics, CNC rotary tables, and aerospace mechanisms.

Details

Leave A Message

Leave A Message
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
Submit

Home

Products

whatsApp

contact