Quick Answer: What are the dimensions and key specifications of a 6205 deep groove ball bearing? The 6205 has a 25 mm bore, 52 mm outside diameter, and 15 mm width. Dynamic load rating is 14.8 kN, static rating 7.8 kN. Reference speed reaches 28,000 r/min, limiting speed 18,000 r/min. Available in open, ZZ, and 2RS variants.
The 6205 deep groove ball bearing is a standardized metric bearing with a bore diameter of 25 mm, an outside diameter of 52 mm, and a width of 15 mm. It belongs to the 62 series of single-row deep groove ball bearings and is one of the most commonly used bearing sizes worldwide.
Whether you are selecting bearings for an electric motor, an automotive wheel hub, a pump, or an agricultural machine, the 6205 offers a versatile solution that combines high load capacity, good speed capability, and reliable performance. But what exactly makes this bearing so widely used? Let us break down everything you need to know – from dimensions and load ratings to seal options, applications, and selection criteria.
Data referenced from ISO 15:2017 standards and leading manufacturer specifications such as SKF and NSK. Values may vary slightly between manufacturers; always consult the specific product technical data sheet for your application.
Basic Dimensions and Specifications of the 6205 Bearing
The 6205 bearing follows standardized boundary dimensions under ISO 15:2017. Here are the complete specifications:
Core Dimensions:
- Inner Diameter (d): 25 mm
- Outer Diameter (D): 52 mm
- Width (B): 15 mm
Rolling Elements:
- Ball Diameter (Dw): 7.938 mm (5/16 inch)
- Number of Balls: 13
- Pitch Circle Diameter (Dpw): approximately 38.5-39.1 mm (varies by manufacturer)
Additional Physical Specifications:
- Shoulder Diameter (d1): approximately 34.35 mm
- Recess Diameter (D2): approximately 46.21 mm
- Chamfer Dimension (r1,2 min.): 1.0 mm
- Product Net Weight: approximately 0.127-0.130 kg
Load Ratings:
- Basic Dynamic Load Rating (C): 14.8 kN
- Basic Static Load Rating (C0): 7.8 kN
- Fatigue Load Limit (Pu): 0.335 kN
Speed Ratings:
- Reference Speed: 28,000 r/min
- Limiting Speed: 18,000 r/min
Tolerances and Clearance:
- Radial Internal Clearance: CN (Normal) standard; C3 (increased) available
- ISO Tolerance Class: P6 (Class 6) and tighter width tolerance
Components and Design Features
The 6205 deep groove ball bearing features a single-row, non-separable design. Its construction includes an inner ring, an outer ring, a cage (retainer), and a complement of rolling elements (balls).
Raceway Groove Design: The raceway grooves are designed with a radius slightly larger than the ball radius, creating a point contact between the balls and the raceways. This design minimizes friction while allowing the bearing to handle both radial and axial forces.
Load-Carrying Capability: The deep raceway grooves and the close conformity between the grooves and the balls enable the 6205 to support axial loads in both directions, even at high speeds. This bidirectional axial load capacity is a key advantage over other bearing types that can only handle axial loads in one direction.
Cage Material (Retainer): The standard cage is made of sheet steel (bearing steel). For specific applications, variants may feature alternative cage materials:
- Sheet steel cage (standard): Suitable for most general-purpose applications
- Machined brass cage (M): Offers higher strength and is often used in high-temperature or heavy-load conditions
- Polyamide (nylon) cage (TN9): Lightweight and quiet, commonly used in electric motors and household appliances
Design Characteristics:
- Simple, versatile, and robust construction
- Low friction and energy-efficient operation
- Optimized for low noise and low vibration
- High-speed capability
- Require little maintenance
- Easy to mount and interchange with other manufacturers’ 6205 bearings
Pairing: In applications requiring minimization of internal axial forces, 6205 bearings are often used in pairs.
Seal and Shield Types for 6205 Bearings
The 6205 bearing is available in several sealing configurations, each suited to different operating environments. Understanding these options is critical for proper bearing selection.
Open (No Suffix):
- No seals or shields on either side
- Grease can flow freely through the bearing for lubrication purposes
- Suitable for applications where external contamination is minimal and where the lubrication system is externally managed
- Offers the highest speed capability among all variants
ZZ (Metal Shields – Double Shielded):
- Metal shields on both sides of the bearing
- Primary function: keep lubricating grease inside the bearing
- Non-contact shielding design creates lower drag compared to contact seals
- Provides effective protection against dust and larger contaminants
- Less effective at excluding water and fine dust compared to rubber seals
- Lower friction than 2RS, making it better suited for higher-speed applications
Z (Single Metal Shield):
- Metal shield on one side only
- Offers protection on one side while leaving the other side open
2RS (Rubber Seals – Double Sealed):
- Rubber seals on both sides
- Provides stronger protection against humidity, water, dust, and other contaminants
- Contact-type sealing offers superior contamination exclusion
- Higher friction than ZZ shields due to contact sealing
- Lower limiting speed compared to ZZ variants
- Ideal for harsh or contaminated environments
Selection Considerations:
- Operating environment: Clean, controlled environments may allow open or ZZ options; dusty, wet, or contaminated environments require 2RS seals
- Speed requirements: Open and ZZ variants offer higher speed capability; 2RS seals have lower limiting speeds
- Maintenance access: Open bearings allow relubrication; sealed bearings are typically grease-filled for life
- Cost: Sealed variants generally cost more than open variants
Key Features of the 6205 Bearing
The 6205 offers several features that make it a preferred choice across industries:
Standardized Metric Dimensions: The 6205 conforms to ISO 15:2017 standards with its 25x52x15 mm format, ensuring global interchangeability. You can source this bearing from any manufacturer with confidence that it will fit your application.
High Load Capacity: The bearing handles substantial radial loads while also supporting moderate axial loads in both directions – a combination not all bearing types can offer.
High-Speed Performance: Reference speed of 28,000 r/min and limiting speed of 18,000 r/min make the 6205 suitable for high-speed applications such as electric motors and spindles.
Low Friction: The point contact between balls and raceways minimizes friction, reducing energy consumption and heat generation.
Low Noise and Vibration: Optimized design ensures quiet operation – critical for applications like household appliances and automotive components.
Durability and Reliability: Robust construction and high-quality bearing steel deliver long service life under demanding conditions.
Versatility: The bearing supports multiple load directions and fits a wide range of industrial applications.
Low Maintenance: Sealed variants are grease-filled for life, requiring no relubrication. Open variants allow for easy relubrication when needed.
6205 Bearing Designation Code Explained
The bearing designation “6205” follows a standardized nomenclature system used by bearing manufacturers worldwide. Here is what each digit means:
“6” – Type Designation:
- Indicates a single-row deep groove ball bearing
- This is the most common and versatile bearing type
“2” – Dimension Series:
- Indicates the 02 series – a combination of width series (0) and diameter series (2)
- This series is characterized by a relatively narrow width (15 mm) for a 52 mm outside diameter
“05” – Bore Diameter Code:
- The bore diameter is calculated by multiplying the last two digits by 5
- 05 x 5 = 25 mm bore diameter
- This coding system applies to bearings with bore diameters from 20 mm to 480 mm
Suffixes (Common Additions):
- ZZ or 2Z: Double metal shields
- 2RS, 2RS1, or DDU: Double rubber seals
- C3: Increased internal clearance (larger than CN)
- NR: Snap ring groove on outer ring
- TN9: Polyamide (nylon) cage
- M: Machined brass cage
Selection Guide for 6205 Bearings
Choosing the right 6205 bearing for your application requires careful consideration of several factors:
Load Requirements:
- Evaluate both radial loads and axial loads your application will impose
- Compare against the basic dynamic load rating (14.8 kN) and static load rating (7.8 kN)
- Consider the fatigue load limit (0.335 kN) for applications with cyclic loading
- For predominantly radial loads, the 6205 performs exceptionally well
Speed Requirements:
- Check reference speed (28,000 r/min) and limiting speed (18,000 r/min) against your operating speed
- Note that sealed variants (2RS) have lower limiting speeds than open or ZZ variants
- Higher speeds may require C3 clearance to accommodate thermal expansion
Size and Fit:
- Shaft abutment diameter (da min.): 30.6 mm
- Shaft abutment diameter (da max.): Refer to the specific manufacturer’s technical data sheet
- Housing abutment diameter (Da max.): 46.4 mm
- Fillet radius (ra max.): 1.0 mm
- Proper shaft and housing fits are critical for bearing performance and life.
Material and Sealing:
- Standard: bearing steel with sheet steel cage
- Choose seal type based on operating environment (see Seal Types section above)
- Consider stainless steel variants for corrosion-resistant applications
Internal Clearance:
- CN (Normal): Standard clearance for most applications
- C3: Increased clearance – recommended for applications with higher operating temperatures, higher speeds, or press fits that reduce internal clearance
- For specific clearance values, refer to the FAQs section below or the manufacturer’s technical documentation
Quality and Reliability:
- Choose bearings from reputable manufacturers that comply with ISO standards
- Look for certifications such as IATF16949 for automotive applications
- Verify compliance with RoHS, REACH, and other relevant standards
Applications of the 6205 Bearing
The 6205 deep groove ball bearing is used across a remarkably wide range of industries and applications:
Electric Motors and Generators:
- One of the most common applications
- Used in both small and medium-sized electric motors
- Provides smooth, efficient operation with low noise
Automotive Industry:
- Wheel hubs and wheel bearings
- Electric power steering systems
- Alternators
- Water pumps
- Transmissions and gearboxes
- Engine components
Pumps and Compressors:
- Centrifugal pumps
- Compressors
- Blowers and fans
Agricultural Machinery:
- Tractors and agricultural equipment
- Plows, seeders, and harvesters
Household Appliances:
- Washing machine drums
- Fans and ventilation units
- Household appliances requiring quiet, reliable rotation
Industrial Machinery:
- Conveyor systems
- Gearboxes and speed changers
- Belt drives and power transmission systems
- Printing and textile machines
- Light-duty industrial equipment
Electric Tools:
- Power drills, grinders, and other handheld tools
Light-Duty Applications:
- Skateboards and bicycles
Conclusion
The 6205 deep groove ball bearing (25 mm bore x 52 mm outside diameter x 15 mm width) is a versatile, standardized metric component that delivers reliable performance across countless applications. With a dynamic load rating of 14.8 kN, reference speed of 28,000 r/min, and availability in open, ZZ, and 2RS configurations, it offers the flexibility to meet diverse operating requirements.
When selecting a 6205 bearing, consider your application’s load (both radial and axial), speed, temperature, and contamination challenges. Match these requirements against the bearing’s specifications and choose the appropriate seal type and internal clearance (CN or C3). Pay attention to proper shaft and housing fits – the abutment dimensions (da min. 30.6 mm, Da max. 46.4 mm) provide essential guidance for correct installation.
For automotive, industrial, and agricultural applications alike, the 6205 remains a solid choice that combines proven reliability with global interchangeability. Whether you need a standard open bearing for a high-speed motor or a sealed 2RS variant for a contaminated environment, the 6205 delivers the performance you can count on.
FAQs
Q: What are the standard dimensions of a 6205 bearing?
A: The 6205 bearing has a bore diameter of 25 mm, an outside diameter of 52 mm, and a width of 15 mm. The ball diameter is 7.938 mm (5/16 inch) with 13 balls per bearing.
Q: What is the difference between 6205 ZZ and 6205 2RS?
A: ZZ indicates metal shields on both sides, which are non-contact and have lower friction but less effective sealing against water and fine dust. 2RS indicates rubber seals on both sides, which provide superior protection against moisture, dust, and contaminants but have higher friction and lower limiting speeds.
Q: What is the difference between C3 and CN (Normal) clearance?
A: CN (Normal) is the standard radial internal clearance for most applications. C3 indicates increased clearance, which accommodates thermal expansion at higher operating temperatures and compensates for press-fit installations that reduce internal clearance. For a 6205 bearing, C3 clearance typically ranges from 13 to 28 microns (µm) depending on the manufacturer.
Q: Can a 6205 bearing handle axial loads?
A: Yes. Deep groove ball bearings like the 6205 can accommodate axial loads in both directions. The deep raceway grooves and close conformity between the grooves and balls enable this bidirectional axial load capacity.
Q: What is the maximum speed of a 6205 bearing?
A: The reference speed is 28,000 r/min and the limiting speed is 18,000 r/min for open variants. Sealed variants (2RS) have lower limiting speeds due to contact seal friction.
Q: What are the dynamic and static load ratings of a 6205 bearing?
A: The basic dynamic load rating (C) is 14.8 kN, and the basic static load rating (C0) is 7.8 kN. The fatigue load limit (Pu) is 0.335 kN.
Q: What does the “6205” designation mean?
A: “6” indicates a single-row deep groove ball bearing. “2” indicates the 02 dimension series. “05” indicates a 25 mm bore (05 x 5 = 25 mm).
Q: What applications is the 6205 bearing used for?
A: The 6205 is used in electric motors, automotive wheel hubs and transmissions, pumps, compressors, agricultural machinery, household appliances, conveyor systems, and many other industrial applications.
Q: Where can I find the abutment dimensions for installing a 6205 bearing?
A: The abutment dimensions are detailed in the Selection Guide section above. Key values include da min. 30.6 mm and Da max. 46.4 mm. Always consult the manufacturer’s technical data sheet for your specific bearing variant.
Q: What cage material is used in a standard 6205 bearing?
A: The standard cage is made of sheet steel (bearing steel). Variants with machined brass (M) or polyamide (TN9) cages are available for specific high-temperature, high-load, or noise-sensitive applications.
