THK RB18025UUCC0P5 Cross Roller Ring
The RB18025UUCC0P5 is a basic‑type crossed roller bearing designed for high‑precision inner‑ring rotation. It features a separable outer ring (held by assembly screws) and an integrated inner ring, with cylindrical rollers arranged orthogonally in 90° V‑groove raceways via precision spacer retainers.
The RB18025UUCC0P5 is a basic‑type crossed roller bearing designed for high‑precision inner‑ring rotation. It features a separable outer ring (held by assembly screws) and an integrated inner ring, with cylindrical rollers arranged orthogonally in 90° V‑groove raceways via precision spacer retainers. This design supports radial, axial, and moment loads simultaneously, delivering 3–4× the rigidity of conventional double‑row thin angular contact bearings. Factory‑equipped with double rubber seals (UU), normal internal preload (CC0), and ISO P5 ultra‑precision, it ensures minimal runout, stable low torque, and reliable contamination protection for heavy‑load precision machinery.
Official Technical Specifications
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Model | RB18025UUCC0P5 | — | UU=double seals; CC0=preload; P5=precision class |
| Inner Diameter (d) | 180 | mm | Integrated inner ring (rotation side) |
| Outer Diameter (D) | 240 | mm | Separable outer ring (1‑piece split) |
| Width (B) | 25 | mm | Total bearing width |
| Roller Pitch Circle Diameter (dp) | 210 | mm | Official design value |
| Shoulder Height (a / b) | 3.5 / 2.0 | mm | Mounting reference (inner / outer) |
| Minimum Chamfer (r₁ min) | 1.5 | mm | Inner/outer ring chamfer |
| Shaft Fit Dia. (ds max) | 195 | mm | Maximum shaft diameter for fit |
| Housing Fit Dia. (Dh min) | 225 | mm | Minimum housing bore diameter |
| Radial Dynamic Load Rating (C) | 84 | kN | THK standard rating (ISO 281) |
| Radial Static Load Rating (C₀) | 143 | kN | THK standard rating (ISO 76) |
| Mass | 3.44 | kg | Exact factory net weight |
| Accuracy Class | P5 | — | Ultra‑precision (ISO 199) |
| Internal Clearance | CC0 | — | Normal preload (minus clearance) |
| Sealing | UU | — | Double rubber contact seals (both sides) |
| Lubrication | Grease | — | Factory‑filled with THK‑specified lithium‑base grease |
Key Design Features
- Extreme Rigidity: Crossed roller arrangement with full‑length spacer retainers eliminates roller skewing, providing exceptional stiffness for heavy‑load precision applications.
- Ultra‑Precision Performance: P5 accuracy ensures minimal radial/axial runout; CC0 preload eliminates internal clearance, critical for high‑repeatability motion control.
- Superior Contamination Resistance: UU double seals prevent dust, chips, and coolant ingress, 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).
- Stable Low Torque: Spacer retainers reduce roller friction and sliding, ensuring consistent, low rotational torque even under light loads and high speeds.
Typical Applications
- Machine tool index tables, rotary worktables, and CNC turrets
- Industrial robot joints, swivel units, and heavy‑duty end‑effector rotary stages
- Precision measuring instruments and optical inspection equipment
- Semiconductor/IC manufacturing machinery (wafer stages, handlers)
- Medical imaging and diagnostic equipment (CT scanners, MRI machines)
Model Decoding (THK Standard)
| Code | Meaning |
|---|---|
| RB | Basic type (separable outer ring, inner ring rotation) |
| 180 | Inner diameter = 180 mm |
| 25 | Width = 25 mm |
| UU | Double rubber contact seals (both sides) |
| CC0 | Normal internal preload (THK standard) |
| P5 | Precision class (ISO P5, ultra‑precision) |
