1 Complete Model & Code Explanation

Model：625-RZTN9/CNHVT105B

Code Definition

625：Basic dimension of miniature deep groove ball bearing

RZ：Single-side non-contact rubber seal

TN9：Glass fiber reinforced polyamide cage

CN：Standard radial internal clearance class

CNHVT105B：Custom high-temperature long-service grease grade

Structure：Single-side non-contact rubber seal, opposite side open without seal

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

Important reminder: 625-RZTN9/CNHVT105B is bearing steel miniature bearing with single-side non-contact rubber seal, suitable for radial loads and moderate bidirectional axial loads. Compared with 2RS contact seals, RZ non-contact seal generates lower friction and allows higher rotational speed, only blocking dry dust. It cannot resist water vapor, oil mist or liquid. The open side has no protection, dust and moisture can easily penetrate through open end. Long-term continuous over-temperature operation is forbidden for TN9 polyamide cage to avoid softening and deformation. Pre-filled CNHVT105B grease adapts to working conditions with obvious temperature rise; seal cannot be removed for on-site re-lubrication.

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：RZ single non-contact rubber seal, opposite side open

Cage：TN9 glass fiber reinforced polyamide cage

Radial internal clearance：CN standard clearance

Material：Bearing steel

Surface coating：Uncoated

Pre-installed lubricant：CNHVT105B special high-temperature 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：76 000 r/min

Limiting speed：50 000 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, highest speed, no protection on both sides

625-RZ：Single non-contact rubber seal, basic dust protection, standard grease

625-2RZ：Double non-contact rubber seals, dust protection on both sides

625-RZTN9：Single RZ seal + TN9 polyamide cage, standard grease

625-RZTN9/CNHVT105B：Single RZ seal, TN9 cage, CNHVT105B high temp grease (this model)

625-2RS：Double contact rubber seals, dust & moisture resistant, lower limiting speed

W 625-RZTN9：Stainless steel version with anti-corrosion property

2 Structure & Operating Characteristics

Japan NMT 625-RZTN9/CNHVT105B is 625 series bearing steel miniature deep groove ball bearing fitted with single-side RZ non-contact rubber seal, TN9 polyamide cage and filled with CNHVT105B high-temperature grease. Developed for high-speed miniature transmission mechanisms with temperature rise and unilateral dust protection demand. Bearing steel features high hardness and stable load capacity without natural rust resistance; overall sealing design is required under humid conditions.

TN9 glass fiber reinforced polyamide cage is lightweight, low noise and possesses good self-lubrication adaptability for long-time high-speed rotation. Continuous operation exceeding temperature limit will cause cage creep and damage. Tiny clearance exists between RZ non-contact seal and inner ring, low friction torque balances dust resistance and high-speed performance, only stopping dry solid dust. The other bearing side is fully open, equipment housing must shield the open end structurally. CNHVT105B special grease delivers superior anti-oxidation and heat resistance compared with general lithium grease, slowing grease carbonization under high temperature. Standard CN radial clearance matches assembly tolerances of most miniature shafts.

The bearing mainly withstands radial loads and tolerates moderate bidirectional axial loads. Never arrange open end toward dust or moisture splash; medium penetration leads to grease deterioration, raceway corrosion and wear. Avoid sustained over-temperature operation to protect polyamide cage.

3 Core Performance Advantages

1. Dimension 5×16×5 mm, single-side RZ non-contact seal, low friction loss, better high-speed performance than contact sealed bearings.

2. TN9 glass fiber polyamide cage provides smooth low-noise operation, light weight and reduces centrifugal load at high speed.

3. Custom CNHVT105B high-temperature grease with anti-oxidation and heat resistance, suitable for motors generating heat during long running.

4. Single-side sealing design saves axial space, ideal for compact equipment with dust risk only on one side.

5. CN standard radial clearance ensures excellent interchangeability for direct replacement of same-size bearings.**

6. Rigid bearing steel substrate supports stable continuous load of small high-speed rotary components.

4 Typical Application Fields

4.1 Small High-Speed Drive Motors

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

4.2 Handheld Precision Power Tools

Spindles of small grinding heads, nail polishing equipment, portable miniature high-speed actuators.

4.3 Instrument & Sensor Equipment

Rotary shafts of laboratory testing instruments, miniature optical gimbals, portable sensing rotary mechanisms.

4.4 Consumer Electronics & Automation Accessories

Built-in transmission of small home appliances, driven wheels for miniature automation conveyors, high-speed model spindles.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

Complete assembly in clean environment to prevent hard particles scratching RZ sealing lip. Press force shall act on proper bearing end face; avoid direct pressure on rubber seal area. Use matching sleeves for uniform pressing to prevent seal extrusion deformation. Strictly control interference fit between shaft and housing. Excessive interference reduces internal clearance, raises temperature at high speed and shortens service life of polyamide cage and grease. Pay attention to assembly orientation: install RZ sealed side facing dust source, open end toward clean cavity.

5.2 Selection Guidance

Clean environment on both sides, maximum rotational speed priority → 625 open type

Dry dust only on single side, equipment generates heat during operation → 625-RZTN9/CNHVT105B (this model)

Dust risk on both sides requiring bilateral dust protection → 625-2RZTN9 with high-temperature grease

Exposed to moisture and oil mist requiring moisture & oil resistance → 625-2RS contact rubber seal version

Humid working condition with anti-rust requirement → W 625-RZTN9 stainless steel series

5.3 Lubrication Instruction

Pre-filled with special CNHVT105B high-temperature grease at factory for long maintenance-free service under normal conditions. RZ seal is crimped non-detachable structure, on-site re-greasing and solvent soaking cleaning are prohibited. Continuous high temperature and long-time overspeed operation accelerate grease oxidation carbonization and cause aging embrittlement of TN9 polyamide cage, drastically shortening bearing service life.

5.4 Environmental Application Notes

RZ non-contact rubber seal only protects against dry dust, incapable of resisting water, mist and oil mist; the opposite open side has the weakest protection. Equipment housing must adopt structural isolation to avoid moisture entering from open end. Bearing steel has no inherent rust resistance; overall moisture-proof design is necessary even if seal is intact under high humidity. Polyamide cage has clear temperature limit; long-term continuous over-temperature running is forbidden.

6 Daily Maintenance & Fault Troubleshooting

Carry out short low-speed running-in after assembly; raise to rated speed only after confirming no abnormal noise and temperature rise. Typical faults of this model: gradually increasing noise, sluggish rotation, rapid temperature rising.

Common failure causes: grease deterioration caused by dust/moisture entering open end, polyamide cage aging from persistent high temperature, wrong assembly orientation, insufficient clearance from over-fit, long-term excessive axial load. Damaged cage, corroded or worn raceways cannot be repaired; replacement with new bearing is recommended upon failure.