THK RB25030UUCC0P5 Cross Roller Ring
The RB25030UUCC0P5 is a basic‑type crossed roller bearing optimized for high‑precision inner‑ring rotation. It features a separable outer ring (secured with assembly screws) and an integrated inner ring, with cylindrical rollers arranged orthogonally in 90° V‑groove raceways via precision spacer retainers.
The RB25030UUCC0P5 is a basic‑type crossed roller bearing optimized for high‑precision inner‑ring rotation. It features a separable outer ring (secured with assembly screws) and an integrated inner ring, with cylindrical rollers arranged orthogonally in 90° V‑groove raceways via precision spacer retainers. This design enables simultaneous support for radial, axial, and moment loads, delivering 3–4× the rigidity of conventional double‑row thin angular contact bearings. Factory‑configured with double rubber seals (UU), normal internal preload (CC0), and ISO P5 ultra‑precision, it ensures minimal runout, stable low torque, and reliable contamination resistance for heavy‑load precision machinery applications.
Official Technical Specifications
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Model | RB25030UUCC0P5 | — | UU=double seals; CC0=preload; P5=precision class |
| Inner Diameter (d) | 250 | mm | Integrated inner ring (rotation side) |
| Outer Diameter (D) | 330 | mm | Separable outer ring (1‑piece split) |
| Width (B) | 30 | mm | Total bearing width |
| Roller Pitch Circle Diameter (dp) | 287.5 | mm | Official design value |
| Shoulder Height (a / b) | 4.5 / 3.0 | mm | Mounting reference (inner / outer) |
| Minimum Chamfer (r₁ min) | 2.5 | mm | Inner/outer ring chamfer |
| Shaft Fit Dia. (ds max) | 269 | mm | Maximum shaft diameter for fit |
| Housing Fit Dia. (Dh min) | 306 | mm | Minimum housing bore diameter |
| Radial Dynamic Load Rating (C) | 126 | kN | THK standard rating (ISO 281) |
| Radial Static Load Rating (C₀) | 244 | kN | THK standard rating (ISO 76) |
| Mass | 8.1 | kg | Exact factory net weight |
| Accuracy Class | P5 | — | Ultra‑precision (ISO 199) for rotation accuracy |
| Internal Clearance | CC0 | — | Normal preload (minus clearance; THK standard) |
| Sealing | UU | — | Double rubber contact seals (both sides) |
| Lubrication | Grease | — | Factory‑filled with THK‑specified lithium‑base grease |
Key Design Features
- Exceptional Rigidity: Crossed roller arrangement with full‑length spacer retainers eliminates roller skewing, providing superior stiffness for heavy‑load precision applications in a compact envelope.
- Ultra‑Precision Performance: P5 class ensures minimal radial/axial runout; CC0 preload eliminates internal clearance, critical for high‑repeatability motion control in indexing and positioning systems.
- Enhanced Contamination Protection: UU double seals prevent dust, chips, and coolant from entering the raceway, extending service life in harsh industrial environments.
- Simplified Installation: Separable outer ring simplifies mounting and alignment; assembly screws maintain ring integrity during installation (remove after mounting per THK guidelines).
- Stable Low Torque: Spacer retainers reduce roller friction and sliding, ensuring consistent, low rotational torque even under heavy loads and moderate speeds.
Typical Applications
- Heavy‑duty machine tool index tables, rotary worktables, and large CNC turrets
- Industrial robot joints, heavy‑load swivel units, and end‑effector rotary stages
- Precision measuring instruments and optical inspection equipment
- Semiconductor/IC manufacturing machinery (large wafer stages, handlers)
- Medical imaging and diagnostic equipment (CT scanners, MRI machines)
- Aerospace and defense precision positioning systems
Model Decoding (THK Standard)
| Code | Meaning |
|---|---|
| RB | Basic type (separable outer ring, inner ring rotation) |
| 250 | Inner diameter = 250 mm |
| 30 | Width = 30 mm |
| UU | Double rubber contact seals (both sides) |
| CC0 | Normal internal preload (THK standard) |
| P5 | Precision class (ISO P5, ultra‑precision) |
