Click to zoom
634ZZ / 634Z Miniature Ball Bearing (4mm x 16mm x 5mm)
- · Inner Diameter: 20mm
- · Outer Diameter: 42mm
- · Width: 12mm
- · Precision Rating: P0 P6 P5 P4 P2
- · Clearance: C0
- · Sealing Type: ZZ
- · Number of Row: Single Row
- · Material: Chrome Steel GCR15
- · Grease RPM Limit: 2000 RPM
- · Lubrication: Grease
Product Overview
High-Precision 634ZZ / 634Z Miniature Deep Groove Ball Bearing
The 634ZZ (634Z) Miniature Ball Bearing is a metric single-row deep groove ball bearing engineered for high-precision, low-vibration, and high-speed rotary applications. Featuring a standard bore size of 4.0mm, an outer diameter of 16.0mm, and a width of 5.0mm, the 634ZZ is a versatile micro component widely utilized in precision robotics, 3D printing mechanisms, and high-speed micro motors.
High-Grade Chrome Steel & Dust Shielded Protection
Manufactured from high-carbon chromium bearing steel (GCr15 / AISI 52100), the inner ring, outer ring, and precision steel balls undergo specialized thermal heat treatment to achieve superior hardness (HRC 60-65) and structural fatigue strength. Equipped with dual non-contact stamped metal shields (ZZ designation), the bearing retains internal factory lubrication while preventing ambient dust, debris, and particulates from entering the raceway.
Low Friction & Smooth High-Speed Performance
Equipped with precision-honed raceway grooves and a balanced steel ribbon cage, the 634ZZ bearing delivers low rotational resistance, low acoustic noise, and smooth running characteristics at speeds up to 43,000 RPM. Its tight dimensional tolerances guarantee smooth radial load support and minimal axial play under continuous operation.
Custom Manufacturing & Material Options
To support specialized industrial and OEM application environments, custom configurations are available upon request:
- Stainless Steel Options: Stainless steel (SUS440C / SUS304) construction for damp, corrosive, or food-grade applications.
- Rubber Sealed Variant: Rubber contact sealed model (634-2RS) available for enhanced liquid and dust protection.
- Flanged Ring Design: Flanged outer ring model (F634ZZ) available for simplified housing mounting and axial location.
- Precision Grading: Available in ABEC-1, ABEC-3, ABEC-5, and ABEC-7 tolerance classes.
Technical Specifications
| Inner Diameter | 20mm |
| Outer Diameter | 42mm |
| Width | 12mm |
| Precision Rating | P0 P6 P5 P4 P2 |
| Clearance | C0 |
| Sealing Type | ZZ |
| Number of Row | Single Row |
| Material | Chrome Steel GCR15 |
| Grease RPM Limit | 2000 RPM |
| Lubrication | Grease |
| Size | 20x42x12mm |
| Certificate | ISO9001 |
| Weight | 0.08(kg) |
Key Features
Applications
