Product Overview

The NMT W 623-2RS1 is a double-sealed, single-row miniature stainless steel deep groove ball bearing. With a 3 mm bore, 10 mm outer diameter, and 4 mm width, this bearing is manufactured entirely from stainless steel (both rings and rolling elements) with a stainless steel stamped cage, equipped with non-contact rubber seals on both sides (2RS1) and pre-filled with high-quality grease. It integrates extreme miniaturization, maintenance-free sealing, high corrosion resistance, and precision rotational accuracy into a single package, accommodating radial and bidirectional axial loads simultaneously.

 

The bearing offers a basic dynamic load rating of 0.358 kN, a static load rating of 0.110 kN, and a fatigue load limit of 0.005 kN. It achieves a limiting speed of 40,000 r/min. The bearing weighs only 2.3 g with an operating temperature range of -40°C to 120°C. Its carbon footprint is extremely low, making it the ideal choice for miniature precision equipment.

 

Model Code Decoding – Understanding NMT W 623-2RS1

Code Meaning

W Stainless steel material – rings and rolling elements made of corrosion-resistant stainless steel

623 Basic series designation, miniature deep groove ball bearing series

-2RS1 Rubber seal on both sides – non-contact rubber seals on both sides

Core Value: The W-series stainless steel material provides excellent corrosion resistance and chemical resistance, performing exceptionally well in humid, corrosive, or high-cleanliness environments. The 2RS1 double rubber seals effectively prevent contaminant ingress while the non-contact design adds no extra resistance or heat generation. The bearing comes pre-lubricated from the factory and is maintenance-free. The stainless steel stamped cage ensures reliable rolling element guidance. The P0 normal precision class combined with CN radial internal clearance ensures low friction, low vibration, and low noise operation even at the 40,000 r/min limiting speed. The synergy of extreme miniaturization, maintenance-free sealing, high corrosion resistance, and precision rotational accuracy makes this bearing the ultimate bearing solution for miniature precision equipment.

 

Core Performance Advantages

1. Double Rubber Seals – Maintenance-Free, Extended Life

The bearing features non-contact rubber seals on both sides (2RS1) that effectively prevent moisture, dust, and other contaminants from entering the bearing interior, while the non-contact design avoids friction between the seal and the inner ring – adding no extra resistance or heat generation. The bearing is pre-filled with high-quality grease at the factory and is maintenance-free – no washing or relubrication is required. This ensures stable temperature performance even at 40,000 r/min high speeds, while significantly extending maintenance intervals and maintaining excellent performance even in harsh environments.

 

2. Stainless Steel Material – High Corrosion Resistance, Extended Life

Manufactured entirely from stainless steel, this bearing provides excellent corrosion resistance and chemical resistance. In humid, corrosive, or high-cleanliness environments, stainless steel bearings effectively resist rust and chemical attack, significantly extending service life. This makes them particularly suitable for food processing machinery, pharmaceutical equipment, marine applications, and chemical processing industries with strict cleanliness and corrosion resistance requirements.

 

3. Precision Miniaturization – 3×10×4 mm

With a compact design – 3 mm bore, 10 mm outer diameter, and 4 mm width – this bearing can be easily integrated into space-constrained precision equipment. Weighing only 2.3 g, it is particularly suitable for miniature devices with extreme space and weight requirements, such as precision instruments, miniature motors, medical devices, and optical scanners.

 

4. 40,000 r/min High-Speed Performance – Industry-Leading

This bearing achieves a limiting speed of 40,000 r/min. The low-friction design and optimized internal geometry ensure stable operation and low heat generation at high speeds. This speed level makes it the ideal choice for high-speed miniature motors, precision instrument spindles, dental handpieces, and other high-speed miniature devices.

 

5. Deep Groove Design – Bidirectional Load Capacity, Excellent Versatility

Deep groove ball bearings feature a simple structure, wide versatility, and low friction. This bearing can accommodate radial loads and bidirectional axial loads simultaneously, providing excellent load capacity in miniaturized designs. With a dynamic load rating of 358 N and static load rating of 110 N, it meets the load requirements of most miniature applications.

 

6. Ultra-Lightweight – Only 2.3 Grams

The bearing weighs only 2.3 g. The extremely low rotating mass effectively reduces centrifugal loads and inertia moments at high speeds.

 

7. P0 Normal Precision + CN Radial Clearance – Versatility and Reliability Combined

This bearing features P0 normal precision class and CN normal radial internal clearance. This combination ensures reliable operation in the vast majority of general miniature applications, while facilitating easy installation and maintenance.

 

8. Stainless Steel Stamped Cage – Speed and Durability Combined

The stainless steel stamped cage provides reliable rolling element guidance and low friction at high speeds, contributing to reduced centrifugal forces, friction, and heat generation – a key factor in achieving the 40,000 r/min limiting speed.

 

9. Wide Operating Temperature Range

This bearing operates within a temperature range of -40°C to 120°C, capable of adapting to various demanding environments from cold storage to high-temperature processing.

 

10. Clear Performance Specifications

 

Parameter Value

Bore d 3 mm

Outer Diameter D 10 mm

Width B 4 mm

Chamfer r₁,₂ min. 0.15 mm

Recess Diameter d₂ ≈ 4.35 mm

Recess Diameter D₂ ≈ 7.98 mm

Dynamic Load Rating C 0.358 kN

Static Load Rating C₀ 0.110 kN

Fatigue Load Limit Pu 0.005 kN

Reference Speed 140,000 r/min

Limiting Speed 40,000 r/min

Ball Material Stainless Steel

Ring Material Stainless Steel

Cage Material Stainless Steel Stamped

Seal Type Double Rubber Seals (2RS1)

Tolerance Class P0 (Normal)

Radial Clearance CN (Normal)

Weight 2.3 g

Temperature Range -40°C to 120°C

Typical Applications

The NMT W 623-2RS1, with its double-sealed protection, high-corrosion-resistance stainless steel material, and compact precision design, covers an exceptionally wide range of high-end miniature applications:

 

Food Processing Machinery – hygiene compliance, corrosion resistance, easy cleaning

 

Pharmaceutical Equipment – critical for contamination risk control, GMP compliant

 

Marine Equipment – seawater corrosion resistance, suitable for harsh humid environments

 

Chemical Processing Equipment – withstands aggressive media, extends maintenance cycles

 

Precision Instruments – measuring devices, optical scanners, chromatography products

 

Miniature Motors – high-speed micro-motors, stepper motors

 

Medical Devices – high-speed dental handpieces, surgical tools

 

Optical Equipment – laser scanners, rotating mirrors, camera focusing mechanisms

 

Semiconductor Manufacturing Equipment – precision wafer processing, chip packaging

 

Industrial Robots – micro high-speed rotary joints

 

Aerospace Micro-Components – micro-actuators, sensors

 

Important Installation Notes

✅ This bearing features double rubber seals (2RS1) and comes pre-filled with high-quality grease – maintenance-free. Ready to install out of the box – no washing or relubrication required.

 

✅ This bearing is manufactured from stainless steel, offering excellent corrosion resistance, particularly suitable for humid, corrosive, or high-cleanliness environments.

 

✅ Ensure shaft and housing fits comply with P0 grade requirements (bore 3 mm, OD 10 mm). Chamfer dimension r₁,₂ min. 0.15 mm.

 

✅ Due to the compact size (only 2.3 g), use specialized miniature bearing installation tools and take extra care to avoid excessive force or impact.

 

✅ Installation in a clean environment is recommended to prevent contaminant ingress that could affect high-speed performance.

 

⚠️ This bearing has no preload setting – if paired configurations or specific preload are required, adjust based on application requirements.

 

⚠️ This bearing has no lubrication groove and no relubrication feature – the rubber seal design is lubricated for life, requiring no relubrication.

 

NMT Quality Commitment

Japan NMT (Enmutī) has deep expertise in the precision bearing industry, with breakthroughs in material purification, process refinement, scenario customization, and intelligent upgrading, transforming precision bearings into core solutions addressing pain points across multiple industries. The NMT W 623-2RS1 bearing is manufactured to strict Japanese quality standards – from ring material (high-purity stainless steel) and rolling elements to superfinishing processes. The combination of stainless steel material (W series), 623 miniature series design, double rubber seals (2RS1), stainless steel stamped cage, P0 precision class, and CN radial clearance makes this bearing the flagship precision bearing in the NMT miniature bearing series – offering the perfect balance of maintenance-free sealing, high corrosion resistance, and precision performance.

 

Choose NMT W 623-2RS1 for:

 

✅ Double rubber seals – maintenance-free, extended life

 

✅ Stainless steel material – high corrosion resistance, extended life

 

✅ Precision miniaturization – 3×10×4 mm, only 2.3 g

 

✅ 40,000 r/min high-speed performance – industry-leading

 

✅ Deep groove design – bidirectional load capacity, low friction, low noise

 

✅ Stainless steel stamped cage – low friction, high speed

 

✅ Wide temperature range – -40°C to 120°C

 

✅ Factory pre-lubricated – ready to install

 

✅ Japanese precision manufacturing quality