THK RU42CC0P5 (XRU42CC0P5) Crossed Roller Bearing
The THK RU42CC0P5 (also designated as XRU42CC0P5) is a compact, high-precision crossed roller bearing belonging to THK's RU series (Integrated Inner/Outer Ring Type with Mounting Holes). This advanced bearing design features cylindrical rollers arranged perpendicular to each other in 90° V-grooves, separated by a precision spacer retainer, enabling it to simultaneously accommodate radial, axial, and moment loads from all directions while maintaining exceptional rotational accuracy and rigidity.
The THK RU42CC0P5 (also designated as XRU42CC0P5) is a compact, high-precision crossed roller bearing belonging to THK's RU series (Integrated Inner/Outer Ring Type with Mounting Holes). This advanced bearing design features cylindrical rollers arranged perpendicular to each other in 90° V-grooves, separated by a precision spacer retainer, enabling it to simultaneously accommodate radial, axial, and moment loads from all directions while maintaining exceptional rotational accuracy and rigidity. The integrated inner and outer ring construction with pre-machined mounting holes on both rings eliminates the need for special flanges or housings, simplifying installation and ensuring stable performance.
Model Coding Explanation
| Code | Meaning |
|---|---|
| RU/XRU | Integrated Inner/Outer Ring Type Crossed Roller Bearing with Mounting Holes |
| 42 | Dimension code (Inner diameter 20 mm, Outer diameter 70 mm, Width 12 mm) |
| CC0 | Radial clearance group (Starting torque: 0.1-0.5 N•m, Radial clearance: 0-25 μm) |
| P5 | Precision class (ABEC-5 equivalent, meeting strict THK accuracy standards for rotational precision) |
Key Specifications
| Parameter | Value |
|---|---|
| Model Number | RU42CC0P5 / XRU42CC0P5 |
| Inner Diameter (d) | 20 mm |
| Outer Diameter (D) | 70 mm |
| Width (B) | 12 mm |
| Roller Pitch Circle Diameter (dp) | 41.5 mm |
| Mounting Holes - Inner Ring | 4 holes, PCD 28 mm, M3 threaded holes |
| Mounting Holes - Outer Ring | 6 holes, PCD 57 mm, φ3.5 through holes with φ6.5 counterbores (depth 3 mm) |
| Basic Dynamic Load Rating (Cr) | 7.35 kN (7350 N) |
| Basic Static Load Rating (Cor) | 8.35 kN (8350 N) |
| Mass | 0.29 kg |
| Precision Class | P5 (Rotational accuracy: Radial runout - 5 μm, Axial runout - 5 μm) |
| Radial Clearance | CC0 group (0-25 μm) |
| Starting Torque | 0.1-0.5 N•m (CC0 group) |
| Material | High carbon chromium bearing steel (SUJ2, JIS G 4805) |
| Sealing Options | Open type (as specified in this model); sealed versions (UU suffix) available |
| Operating Temperature Range | -20°C to +110°C |
| Rotation Capability | Suitable for both inner-ring rotation and outer-ring rotation applications |
| Width Tolerance | 0 to -75 μm (THK official tolerance specification) |
Structural Features
- Integrated Inner/Outer Ring Design: Both rings are one-piece construction, eliminating the need for special flanges or housings, providing exceptional rigidity and stability compared to split-ring designs. This structure ensures minimal deformation under load and maintains consistent rotational accuracy.
- Face-Mount Configuration: Pre-machined mounting holes on both rings allow direct bolting to equipment, simplifying installation and reducing assembly time. Mounting has virtually no effect on performance, ensuring stable, accurate rotation and torque.
- Crossed Roller Arrangement: Ensures uniform load distribution across all rollers, maximizing load capacity while minimizing overall bearing size. This design provides 3-4 times higher rigidity than traditional ball bearing arrangements.
- Spacer Retainer Technology: Prevents roller contact and cage locking, improving reliability, reducing friction, and extending service life compared to traditional steel plate retainers. The retainer also ensures proper roller alignment for smooth, precise rotation.
- Dual-Direction Load Capacity: Capable of handling radial, axial, and moment loads simultaneously from any direction, making it ideal for complex motion applications.
Applications
The RU42CC0P5 is ideally suited for applications requiring compact dimensions, high rigidity, and precise rotation control:
- Industrial robot joints and rotary components
- Precision rotary tables for machine tools and metrology equipment
- Medical devices (e.g., diagnostic scanners, surgical robots, imaging systems)
- Semiconductor and IC manufacturing equipment
- Measuring instruments and optical devices
- Small precision automation systems and manipulators
- Compact rotary indexing tables and positioning mechanisms
Installation & Maintenance Guidelines
- Mounting: Secure directly to equipment using appropriate M3 bolts for the inner ring and matching bolts for the outer ring without special housing or presser flanges. Ensure mounting surfaces are flat, parallel, and clean to maintain bearing accuracy.
- Preload: Factory-set CC0 radial clearance provides optimal performance for most applications; additional preload can be applied if required by specific operating conditions following THK's technical guidelines.
- Lubrication: Open type requires initial grease lubrication (THK recommended: lithium soap-based grease with appropriate viscosity); sealed versions (UU suffix) are factory-lubricated for life under normal operating conditions.
- Operating Limits: Avoid shock loads and excessive speeds beyond rated capacity to ensure maximum service life and maintain precision performance.
- Accuracy Assurance: Mounting surfaces should have a flatness tolerance of ≤ 2 μm and parallelism tolerance of ≤ 3 μm to maintain the bearing's P5 class rotational accuracy (radial runout ≤ 5 μm, axial runout ≤ 5 μm).
