THK LMF30UU Linear Bushing
The THK LMF30UU is a high-precision linear ball bushing with an integrated round flange, engineered for smooth, low-friction linear motion. Its one-piece flange design allows direct and rigid mounting to machine housings, simplifying installation and ensuring stable guidance. Fitted with double lip seals (UU type) on both ends, it offers excellent protection against dust, contaminants, and lubricant leakage, making it ideal for automated machinery, precision instruments etc.
The THK LMF30UU is a high-precision linear ball bushing with an integrated round flange, engineered for smooth, low-friction linear motion. Its one-piece flange design allows direct and rigid mounting to machine housings, simplifying installation and ensuring stable guidance. Fitted with double lip seals (UU type) on both ends, it offers excellent protection against dust, contaminants, and lubricant leakage, making it ideal for automated machinery, precision instruments, semi-conductor equipment, and various linear motion systems requiring reliable performance and long service life.
Official Specifications
| Parameter | Value | Unit |
|---|---|---|
| Inscribed Bore Diameter (dr) | 30 | mm |
| Bore Diameter Tolerance | 0 / -0.010 | mm |
| Outer Diameter (D) | 45 | mm |
| Outer Diameter Tolerance | 0 / -0.016 | mm |
| Overall Length (L) | 64 | mm |
| Length Tolerance | ±0.3 | mm |
| Flange Diameter (D₁) | 70 | mm |
| Flange Diameter Tolerance | 0 / -0.2 | mm |
| Flange Thickness (H) | 10 | mm |
| Number of Ball Rows | 6 | — |
| Basic Dynamic Load Rating (C) | 1420 | N |
| Basic Static Load Rating (C₀) | 2260 | N |
| Mass | 430 | g |
| PCD (Mounting Hole Circle) | 60 | mm |
| Mounting Hole (d₁×d₂×h) | 5.5×9.2×5.4 | mm |
| Radial Clearance | Standard (-9 μm) | μm |
| Maximum Eccentricity | 15 | μm |
| Flange Perpendicularity | 15 | μm |
| Seal Type | Double Lip Seals (UU, both ends) | — |
| Operating Temperature Range | -15°C to +80°C | °C |
| Material (Outer Sleeve/Balls) | High-Carbon Chromium Bearing Steel (SUJ2) | — |
| Retainer Material | Synthetic Resin | — |
| Standard Lubrication | Factory pre-lubricated with grease | — |
| Type | Closed Type | — |
Key Features
- Integrated Round Flange: One-piece structure for secure, flush mounting directly to equipment housings, simplifying assembly and ensuring precise alignment.
- 6-Row Ball Configuration: Provides high radial load capacity, exceptional rigidity, and smooth, stable linear movement.
- Dual UU Seals: Effectively prevents lubricant leakage and blocks the ingress of dust and chips, significantly extending service life in harsh environments.
- High Precision: Manufactured to strict tolerances, ensuring minimal radial clearance and eccentricity for quiet, accurate operation.
- Durable Construction: Utilizes hardened SUJ2 bearing steel for the outer cylinder and balls, offering superior wear resistance.
- Temperature Constraint: Equipped with a resin retainer; continuous operating temperature must not exceed 80°C to maintain material integrity.
Official Application Notes
- Shaft Requirements: Recommended shaft hardness is 60–64 HRC with a surface roughness of Ra ≤ 0.8 μm.
- Load Direction: Designed primarily for radial loads; not suitable for pure moment or axial loads.
- Alignment: Ensure proper shaft alignment to avoid binding and premature wear.
- Model Variants: Available in a long type (LMF30LUU) for increased stability and stainless steel versions for corrosive environments.
