1 Complete Model & Code Explanation

Model：625-2RZTN9/HC5C3WTF1

Code Definition

625：Basic dimension of miniature deep groove ball bearing

2RZ：Double-side non-contact rubber seal

TN9：Glass fiber reinforced polyamide cage

C3：Increased radial internal clearance class

HC5C3WTF1：Wide temperature low-temperature resistant long-life grease grade

Structure：Non-contact rubber seals installed on both ends, no open end

Supply form：Single independent bearing, no factory duplex grinding, DB/DF duplex arrangement not supported

Important reminder: 625-2RZTN9/HC5C3WTF1 is bearing steel miniature bearing with double-side non-contact rubber seal, capable of bearing radial loads and moderate bidirectional axial loads. Compared with 2RS contact seals, double-sided 2RZ non-contact seals feature lower running resistance and higher limiting speed, blocking dry dust on both sides. The seal only prevents dry solid dust and cannot resist water vapor, oil mist or liquid medium. TN9 polyamide cage has temperature limit; long-term continuous over-temperature operation is forbidden to avoid softening and creep deformation. Pre-filled HC5C3WTF1 wide-temperature grease suits applications with obvious ambient temperature fluctuation. Seals are crimped and non-detachable; on-site re-lubrication is not available.

Basic Parameters

Bore d：5 mm

Outer diameter D：16 mm

Width B：5 mm

Bearing type：Single-row deep groove ball bearing

Number of rows：Single row

Bore form：Straight cylindrical bore

Seal arrangement：2RZ double non-contact rubber seal, both ends enclosed

Cage：TN9 glass fiber reinforced polyamide cage

Radial internal clearance：C3 increased clearance

Material：Bearing steel

Surface coating：Uncoated

Pre-installed lubricant：HC5C3WTF1 wide temperature low-temperature special grease

Relubrication capability：On-site re-greasing unavailable

Duplex arrangement：Not supported, single unit operation only

Basic dynamic load rating：0.088 kN

Basic static load rating：0.036 kN

Reference speed：79 000 r/min

Limiting speed：53 000 r/min

Net weight：0.00024 kg

Indicative carbon footprint：0.00060 kg CO₂e

eClass code：23-05-08-01

UNSPSC code：31171504

Series Suffix Comparison

625：Fully open type, maximum rotational speed, no dust protection

625-RZTN9/CNHVT105B：Single RZ seal, CN standard clearance, high temperature grease

625-2RZTN9：Double 2RZ seal, TN9 cage, standard general grease

625-2RZTN9/HC5C3WTF1：Double 2RZ seal, TN9 cage, C3 clearance, wide temperature low temp grease (this model)

625-2RS：Double contact rubber seal, dust and moisture resistance, lower permissible speed

W625-2RZTN9：Stainless steel double sealed version with anti-corrosion property

2 Structure & Operating Characteristics

Japan NMT 625-2RZTN9/HC5C3WTF1 is 625 series bearing steel miniature deep groove ball bearing fitted with double-side 2RZ non-contact rubber seals, TN9 glass fiber reinforced polyamide cage and filled with HC5C3WTF1 wide-temperature grease. It is developed for high-speed miniature transmission components exposed to dust on both sides and obvious working temperature variation. Bearing steel substrate delivers high hardness and stable load capacity without inherent rust resistance; extra housing sealing is required under high humidity.

TN9 glass fiber polyamide cage is lightweight, low vibration and low noise, suitable for continuous long-time high-speed rotation. Continuous operation beyond temperature limit will cause cage deformation and aging. Tiny clearance exists between 2RZ sealing lips and inner ring to reduce rotational friction, realizing dust protection on both sides. Different from ordinary high-temperature grease, HC5C3WTF1 special grease balances low-temperature startup performance and high-temperature oxidation resistance, ideal for alternating hot and cold environments. C3 increased radial clearance compensates thermal expansion caused by temperature rise during high-speed rotation and prevents bearing seizure from insufficient clearance.

The bearing mainly withstands radial loads and tolerates certain bidirectional axial loads. It must be noted that 2RZ seals cannot block water and mist. Complete housing sealing is required if water vapor penetration exists. Long-term overspeed and over-temperature continuous operation are prohibited.

3 Core Performance Advantages

1. Dimension 5×16×5 mm, double-side 2RZ non-contact seals for full end dust protection, low friction and superior high-speed performance over double contact sealed bearings.

2. TN9 glass fiber reinforced polyamide cage ensures smooth low-noise operation, lightweight design reduces centrifugal load at high rotating speed.

3. HC5C3WTF1 wide-temperature special grease supports low-temperature startup and anti-oxidation, adapting to alternating high-low temperature conditions.**

4. C3 increased radial clearance offsets thermal expansion at high speed and effectively avoids bearing locking.

5. Integrated double-sided sealing structure with no assembly orientation, simplifying assembly for compact equipment.

6. Rigid bearing steel material and good interchangeability for retrofitting and replacement of various small high-speed rotary mechanisms.

4 Typical Application Fields

4.1 Small High-Speed Drive Motors

Miniature cooling fan motors, portable air pump motors, small brushless drive spindles.

4.2 Handheld Precision Power Tools

Mini nail polish grinders, small engraving spindles, handheld high-speed polishing assemblies.

4.3 Laboratory & Testing Instruments

Rotary shafts of portable optical gimbals, rotating mechanisms for miniature analytical instruments, transmission parts of environmental sampling equipment.

4.4 Automation & Small Home Appliances

Miniature automation conveyor wheels, rotating shafts of precision office equipment, small household high-speed transmission accessories.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

Complete assembly in clean environment to prevent hard foreign particles scratching both RZ sealing lips. Apply press force onto bearing end face; direct extrusion on rubber seal area is forbidden. Use matching sleeves for uniform pressing to avoid seal lip damage. Control tolerance between shaft and housing properly. Bearings with C3 clearance fit high-speed applications with noticeable temperature rise; excessive interference fit will offset the advantage of increased clearance. The symmetrical 2RZ double seal design has no specific installation direction.

5.2 Selection Guidance

Clean working environment, priority for maximum rotational speed → 625 open bearing

Dust only on single side with high operating temperature → 625-RZTN9/CNHVT105B

Dry dust on both sides, large temperature fluctuation and high-speed operation → 625-2RZTN9/HC5C3WTF1 (this model)

Dust on both sides accompanied by water vapor and oil mist → 625-2RS contact seal version

High humidity environment requiring rust prevention → W625-2RZTN9 stainless steel series

5.3 Lubrication Instruction

Pre-filled with HC5C3WTF1 wide-temperature long-service grease at factory, supporting long maintenance-free operation under standard conditions. The 2RZ seal is permanently crimped non-detachable construction. On-site re-greasing and cleaning with organic solvent are strictly prohibited. Long-term overspeed operation and extreme sustained high temperature accelerate grease deterioration and embrittlement of TN9 polyamide cage, shortening service life significantly.

5.4 Environmental Application Notes

Double-side 2RZ non-contact rubber seals only defend dry solid dust, incapable of resisting water, water mist and oil mist erosion. Bearing steel has no natural anti-rust property. Even with intact double seals, full housing moisture-proof sealing is necessary under high humidity. Polyamide cage has limited operating temperature range; prolonged operation beyond temperature threshold is not allowed.

6 Daily Maintenance & Fault Troubleshooting

Perform low-speed running-in test after assembly; increase to working speed only after confirming no abnormal noise and temperature rise. Typical faults of this model include gradually amplified rotating noise, sluggish rotation and abnormal temperature surge.

Common failure triggers: grease deterioration caused by slow penetration of moisture, cage aging from sustained high temperature, insufficient clearance due to improper fitting tolerance, continuous excessive axial load. Damaged cage, raceway corrosion and spalling cannot be repaired; replacement with new bearing is recommended upon failure.