6304 2RS C3 KOYO 20x52x15 Deep Groove Ball Bearing

KOYO 6304 2RS C3 20x52x15 mm - Sealed Deep Groove Ball Bearing

KOYO 6304 2RS C3 20x52x15 mm is a single-row deep groove ball bearing manufactured by KOYO, a bearing brand of JTEKT. It features a 20 mm bore diameter, 52 mm outside diameter and 15 mm width. The bearing is equipped with rubber contact seals on both sides (2RS) and increased C3 radial internal clearance. Its construction is designed to accommodate radial loads and axial loads in both directions.

Product Characteristics

KOYO 6304 2RS C3 belongs to the 6300 series of single-row deep groove ball bearings, widely used in industrial machinery and rotating mechanical assemblies.

The two contact seals help retain lubricant inside the bearing and reduce the entry of external contaminants.

C3 radial internal clearance is greater than normal clearance and allows for changes in operating clearance caused by mounting conditions and temperature differences.

Key features:

• Manufacturer: KOYO, a JTEKT brand.

• Bearing designation: 6304 2RS C3.

• Single-row deep groove ball bearing.

• Nominal dimensions: 20x52x15 mm.

• Two rubber contact seals (2RS).

• Increased radial internal clearance (C3).

• Factory lubrication typical of standard sealed 2RS bearings.

• Suitable for radial and axial loads.

• Designed for rotating shafts and mechanical assemblies.

Technical Specifications

Reference catalogue values for the KOYO 6304 2RS bearing from JTEKT technical data. The C3 version differs in radial internal clearance. Product-specific specifications for KOYO 6304 2RS C3 should be confirmed against current manufacturer documentation before use in engineering calculations.

What Does KOYO 6304 2RS C3 Mean?

Each part of the bearing designation identifies an important technical characteristic.

6304 - single-row deep groove ball bearing from the 63 dimension series, with a 20 mm bore diameter.

2RS - two rubber contact seals, one fitted on each side of the bearing.

C3 - radial internal clearance greater than normal (CN).

KOYO - a Japanese bearing brand belonging to JTEKT.

The complete designation 6304 2RS C3 should be retained when selecting a replacement bearing.

2RS Seals - Protection Against Contamination

The KOYO 6304 2RS C3 bearing is fitted with contact seals on both sides.

Their main functions are to:

• Help retain grease inside the bearing.

• Reduce the entry of dust and fine particles.

• Protect the rolling elements and raceways against contamination.

• Support operation with factory-applied lubricant.

• Reduce maintenance requirements in suitable applications.

Contact seals produce additional friction compared with open bearings.

They do not provide complete waterproofing or guarantee resistance to high-pressure washing.

C3 Radial Internal Clearance - Meaning and Benefits

C3 indicates radial internal clearance greater than normal clearance (CN).

Bearing internal clearance can change during installation and operation because of:

• Interference fits between the bearing rings and mating components.

• Temperature differences between the shaft and housing.

• Thermal expansion.

• Applied loads.

• Operating speed.

Increased C3 clearance may be required where installation conditions or operating temperatures are expected to reduce the bearing's internal clearance.

However, C3 is not automatically the best choice for every application.

A C3 bearing should not automatically be replaced with a normal-clearance bearing, or vice versa.

The correct clearance class must be selected according to the equipment manufacturer's requirements.

Does C3 Mean Higher Precision?

No.

C3 describes the bearing's radial internal clearance, not its manufacturing accuracy or precision class.

A bearing with C3 clearance is not necessarily more precise than one with normal clearance.

Radial and Axial Load Capacity

The KOYO 6304 deep groove ball bearing is primarily designed to accommodate radial loads.

Its deep raceway geometry also enables it to support axial loads in both directions.

The permissible axial load depends on operating conditions, internal clearance, speed and lubrication.

For applications involving high axial loads, the suitability of a deep groove ball bearing should be verified through engineering calculations.

Typical Applications of KOYO 6304 2RS C3 Bearings

Deep groove ball bearings with dimensions of 20x52x15 mm are widely used in industrial and mechanical equipment.

Typical applications include:

• Electric motors.

• Industrial fans and blowers.

• Pumps.

• Gearboxes and mechanical drives.

• Agricultural machinery.

• Manufacturing equipment.

• Material handling systems.

• Rotating shaft assemblies.

These are general applications of the 6304 bearing series.

The suitability of the specific 2RS C3 version must be confirmed for each machine.

KOYO 6304 2RS C3 vs 6304 2RS, 6304 ZZ C3 and 6304 C3

Bearings with identical nominal dimensions may differ in sealing arrangements and internal clearance.

All these versions have nominal dimensions of 20x52x15 mm.

However, differences in sealing construction and internal clearance may affect suitability for a particular application.

Always compare the complete bearing designation when selecting a replacement.

How to Select the Correct KOYO 6304 2RS C3 Bearing

Before ordering, verify:

1. Shaft diameter - 20 mm.

2. Housing bore diameter - 52 mm.

3. Bearing width - 15 mm.

4. Bearing type - single-row deep groove ball bearing.

5. Double-sided contact seals - 2RS.

6. Increased radial internal clearance - C3.

7. Required radial and axial loads.

8. Operating speed.

9. Temperature and contamination conditions.

10. Equipment manufacturer specifications.

Dimensions alone are not sufficient to confirm interchangeability.

Installation Guidelines

Correct installation is essential for reliable bearing operation.

Basic recommendations:

• Inspect the shaft and housing before installation.

• Verify dimensional tolerances and fits.

• Use clean tools and working surfaces.

• Never transmit mounting force through the rolling elements.

• When mounting onto a shaft, apply force to the inner ring.

• When mounting into a housing, apply force to the outer ring.

• Avoid damaging the 2RS seals.

• Do not remove factory-installed seals unless specifically instructed by the manufacturer.

• Verify correct seating and free rotation after installation.

Incorrect mounting may cause raceway damage, increased vibration, excessive noise and premature bearing failure.

Frequently Asked Questions

What are the dimensions of KOYO 6304 2RS C3?

The bearing measures 20x52x15 mm, with a 20 mm bore diameter, 52 mm outside diameter and 15 mm width.

What does 2RS mean?

2RS indicates two rubber contact seals, one on each side of the bearing.

What does C3 mean?

C3 indicates radial internal clearance greater than normal clearance.

Is KOYO 6304 2RS C3 a deep groove ball bearing?

Yes. It is a single-row deep groove ball bearing.

Is the bearing factory lubricated?

Standard KOYO 6304 2RS bearings are supplied as sealed, grease-lubricated units. The exact grease type and quantity for a specific version should be verified using manufacturer documentation.

Can 6304 2RS replace 6304 2RS C3?

Not without checking the required internal clearance. A version without the C3 suffix may have normal radial internal clearance.

Is 6304 ZZ C3 interchangeable with 6304 2RS C3?

Both bearings have the same nominal dimensions and C3 clearance, but their protective arrangements differ. ZZ uses metal shields, while 2RS uses rubber contact seals.

Can the bearing accommodate axial loads?

Yes. Single-row deep groove ball bearings can accommodate axial loads in both directions within the limits determined by their design and operating conditions.

Does C3 indicate a higher precision class?

No. C3 specifies radial internal clearance, not bearing precision.

Is this bearing suitable for electric motors?

Bearings from the 6304 series are commonly used in electric motors. The suitability of the 2RS C3 version depends on the specific motor's requirements.

Are KOYO and JTEKT the same manufacturer?

KOYO is a bearing brand of JTEKT, a Japanese manufacturer of bearings and automotive components.

Does KOYO 6304 2RS C3 require regular relubrication?

Standard sealed 2RS bearings are designed to operate with factory-applied grease. Relubrication requirements depend on the specific construction and manufacturer recommendations.

What is the difference between C3 clearance and normal clearance?

C3 provides greater initial radial internal clearance than the normal CN class. The correct choice depends on fits, temperatures and operating conditions.

Can the seals be removed?

The seals are factory-installed components. Removing them may damage the sealing system or compromise lubricant retention and contamination protection.

KOYO 6304 2RS C3 - Key Technical Information

KOYO 6304 2RS C3 is a single-row deep groove ball bearing measuring 20x52x15 mm. It features two rubber contact seals and increased C3 radial internal clearance. The bearing accommodates radial loads and axial loads in both directions. Correct replacement selection requires verification of both the sealing arrangement and internal clearance class.

KOYO Bearings at simmering.pl

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